Hello!
Is there a way in the game leading to a happy ending between Adkin Chambers and Lady Druella,
if you are not playing an melee charakter?
My Character only has dodging and throwing.
A NPC that gives a hint to Lady Druellas position for example?

Unfortunately, I don't believe so. If I recall, even if you head to where she's supposed to be, the event won't trigger without having spoken with Sir Garrick first.

If you're short on points, you can always do the (somewhat lengthy, especially if you don't have Teleportation) gods' quest. The bonus upon completion includes three ranks of both Dodge and Melee (along with a whole slew of other bonuses, making you extremely OP) which means you'd need to invest only two more points to qualify for Melee mastery.

Thanks for your answer and the good tipp!