I refuse to take the oath for the empire since they kill innocent men because it is more convenient.

I refuse to aid the Stormcloaks because they are racists.

I killed Astrid, leader of the Dark Brotherhood, because she tried to blackmail me.

I can't steal the mead from the Tavern because i get labeled as a thief in my own town...

I won't drink the blood and turn into a Werewolf, and thus, the companions won't give me quests.



Should i just finish the main quest and be done with the game on any future basis because
most of the quests goes against my own morale ?.

There is lots to do. You are not the only one who wants to play a "clean" character. I do, too. I killed Astrid because I did not want to murder. I DID kill the lady in Riften who was abusing those kids--you did, too.
There are many quests where you are helping others, doing the right thing, etc. Play that role, if that is who you are. That is what I am doing. Did the same thing in Oblivion. (BTW, in Oblivion, even the murders in DB didn't feel too bad. Most fought you and ALL were people who had done bad things to nice people.

Ignore the main quest and just go exploring. Snuff out bandit dens, help out people in need, do bounties for the Jarls. Plenty of things to do.

There's still tons of things to do.Explore,do Deadric quests,do dungeon quests,Thieves Guild,College of Winterhold,more and more quests.

MASSIVE SPOILER.






















When Kodlak Whitemane dies near the conclusion of the Companions questline, you have the option to rid yourself and his spirit of lycanthropy, thus curing yourself.

Did you speak to a guard after killing Astrid? There's a minor quest to kill the rest of the brotherhood - sounds like you might want to do that.