It would take many more gnomes. I do also assume it's a tv movie, and one of the three worst kinds. The cheap formulaic ones that get produced at industrial rates to fill up private channels schedules. You know the kind :

a) The 11pm pseudo-sexy thriller necessarily titled after some variation on "lethal attraction", "mortal relationship", "dangerous flirt" or "tits of death".

b) The afternoon based-on-a-true-story film which summary starts with "Sandy Suburba had everything to be happy, an expensive house, a wealthy dentist husband, and a new washing machine, but when she started to suspect [...]" and titled along the lines of "my daughter is a drug addict", "my husband the man-eater", "my son the motherfucker".

c) The 8pm syfy disaster movie with pre-Amiga CGI and a divorced couple reunited by a plane crash, a swarm of giant insects or a black hole on a collision course with the milky way due to a short-circuited satellite having pushed saturn's rings into the orbit of Ursa Major. It's usually called "Apocalypse Cataclysm Alert" but the words may be swapped around sometimes.

IMDB is not big enough to list all of them.

Ummmmm....."Steel Magnolias"?

Not even close. And too many women in it too. Mine was simple, one plot, one guy, the partner girl who was a close friend that also joked with him throughout the movie about the stalker and finally saved his life.

I like a good puzzle, but in this case...

One the one hand, you offer so many details.
(EDIT:or maybe "many" is too enthusiastic phrased. May be better worded, if I say, you offer enough
details, which usually would help to find something)
On the other hand, no combination of these details returns any result, if searched by Google.

That's never a good sign.
Either that movie/TV-series is really obscure,...or you misremember your details, respectively mix up different movies.

I'm really feverishly anticipating the solution to your problem (if there ever will be one). When you say "detective", do you mean a police detective, or a private eye?
And are you sure about "Diane"/"Diana"? This sounds so ridiculous. You sure, you want to see this again?
And why do you remember this particular scene so well? ;o)
Oh and - were the boobs actually shown?
Because I'm not sure, if that would be possible in a US TV-series (as you suggest below) Again, this sounds ridiculous - if she is a psycho, and he gets stalked by her...why would he shower with her?
This sounds all so wrong. Must've been a "direct-to-DVD" release. So, like a bazillion other movies. That doesn't really help, I'm afraid. Yeah, could be (some doubts, because of "boobs"scene - see above).
Have you tried "Moonlighting", "Remington Steele", etc.? They sometimes had "strange", dreamlike episodes.
Well, and "Sledge Hammer!", with his partner "Dori" (hint, hint, nudge, nudge), of course.

@BreOl72 I've had trouble with other movies where I knew enough details but Google couldn't do anything. For example, All Over Again (2001) aka Against Time (2007) in the US. The movie was about a boy visited by his future self and they have to build a time machine successfully. The plot is original enough but the movie has a low imdb score. Second example, British dark comedy series Murder Most Horrid where Dawn French plays a different role each episode. Original idea. Guess what, Google couldn't find it either.

About the nudity part, I described the boobs jokingly to the guy asking a picture & description of them. In the same timeframe I saw Love, Cheat & Steal with Eric Roberts and Palmetto with Woody Harrelson where similar scenes exist. I didn't remember exactly how each pair of boobs looked like, I just played along with the guy asking. Similar nudity was in the Melrose Place series. Or La Femme Nikita. These movies were aired in Romania at 8 or 9 PM. Sometimes at 10PM but they would rotate. Really erotic ones like Emanuelle were at midnight, 1AM, something like that.

My guy was a police detective, I thought having a partner would imply that, sorry. And for some reason the name Diane/Diana stuck with me, I guess he often called her by name. He doesn't know the blonde is a psycho, he thinks she still has a silly crush on him and is willing to take advantage while it lasts. He even jokes about this with his partner. She goes nuts when she realises he is not serious.

Why would I want to see this again? Why not, I'm revisiting movies I saw & games I played in that time. Call it nostalgia if you like.

If you have more TV series that could match please let me know. I too think it might be an episode of something because a similar "movie" where I had "enough" details was the episode To Tell The Truth, from The Outer Limits. At this point I've pretty much found most of the stuff I remember clearly, this is one of the last ones. I agree memories can mix together but not on this one.

Have you checked in here ?

http://evilbabes.wikia.com/wiki/EvilBabes_Wiki

That's the thing, I don't know (or at least recall) her name. I've seen her in some movies in side-roles, mostly in some comedies probably but I think she was more sinister in some other movie(s). I am not quite sure but I do seem to recall her at least in one "a bit insane and jealous ex-girlfriend" role. but not fully sure...

I have lots of such actors and actresses in mind which I easily recognize and remember by their looks, but don't quite remember in what movies (or even TV series) I've seen them, nor their name...

EDIT: I've decided to find out who she was, no matter if she really was in such a movie. Googling for "wacky blonde actresses" gives all kinds of interesting lists...

Maybe you remember one of her movies? Then look at the actors list.

OK so definitely a straight-to-DVD / TV movie. Because at http://tvtropes.org/pmwiki/pmwiki.php/Main/SexyCoatFlashing the only such movie is Widow on the Hill, from where they got the picture of Natasha Henstridge flashing someone. Its link is red, no other movies match. And I already knew that one anyway.

Traci Lords by any chance? She has a lot of wacky movies about serial killers, gang wars, drugs etc.

Nah, not Traci. I am quite familiar with her because she allegedly has a black belt (or at least the 1st kyu) in Bujinkan Budo Taijutsu. I always found that kinda interesting, considering her image otherwise (and because I have trained BJJ for years as well; I would have loved to train with Traci some throws and holds and such).

But now that you mention it, the other actress actually looks a bit like Traci, with "similar" perky and pointy facial features. But now I think it may be she was mostly in some (early?) 2000s movies, not sure if she was already in the 1990s much.

EDIT: And now I saw you mentioned it even might have been an episode in a TV series? Ok then I am at loss, I thought you were certain it was some movie you saw.

Traci actually has some pretty wacky 90s movies if you look at the trailers, serial killers, killer androids, drug gang wars etc. I ran through her list of movies and nothing matches mine though.

Honestly, I'm not sure on my movie, but I think it's 90% a TV movie and 10% an episode of something.

The only case where I thought an episode was a movie was with The Outer Limits, S4E14 To Tell The Truth. But on that one, I remembered it was pretty short and having found a guy online with weekly TV schedule magazines from way back, I saw it was there, looked quickly at Wiki's list of episodes searching for "alien" and found it. That guy has almost all weeks for 97-99 (helped me find quite a few, had many titles listed in English fortunately), but I think I saw this one from 2000 onward sometime.

Problem is, I don't have an actor or unique character name (like Christopher Lambert's character Augustine in Why Me, which I saw around the same time). Silk Stalkings looked like it was airing back then, an episode kinda matches but it's not mine.

Well, if it was American production from two decades ago or so and there was a flashing scene with bare tits and ass and who knows what, then I presume it is safe to say it was not a TV series, most probably.

Sure we nowadays have Game of Thrones with tits and ass (covered with blood), but back then when we were younger, everything was so pure and innocent on the (American) TV. I bet even MacGyver had never kissed a girl.

EDIT: Ok not sure about "Silk Stalkings", I remotely remember some such TV series, but did it have actual nudity either, or merely innocent "ooh she has black stockings, I think I came into my pants".

I don't think Silk Stalkings had such nudity. I didn't even didn't realise TV series would not have nudity, while only movies would. I simply looked for TV series that would match since the experience with that Outer Limits episode. And Silk Stalkings' characters look like my detective & his partner (the girl more, the guy is younger here). Their episode with a female stalker only has pink lingerie though: https://www.youtube.com/watch?v=t-skuwN-elk&list=PL6A-fAHq28W2tlmIuYeDTG6x1EPWCj7Nh&index=21 minute 42:32.

I've been able to Google other TV movies like "As Good As Dead" or "The People Next Door" just off of a name & plot, but not this one, yet.

Why would nudity occur in movies and not in regular shows?