By AVOIDING the person who's abusing you.
Assuming there's no physical abuse happening.... (if it's happening, get away from this person FAST without thinking twice)...
If this is a boyfriend / girlfriend... get out of the relationship, and do it fast... please, for your own sanity. Get therapy if you've lost your self esteem because of the abuse. Don't think you can "change" this person by marrying him / her. People do change after marriage, but its usually for the worse! And an abuser will DEFINITELY change for the worse.
In a marriage, where the stakes are higher (kids, finances etc), first explore the option of couples counselling. Keep a definite time frame in mind. If it works, excellent. If it doesnt work, decide how badly the abuse is affecting you. Can you live with it? If not, leave. You are a great person and deserve respect.
If its a close friend who's doing this, talk it over. Tell him or her how it hurts and that he / she must stop. Give this person time to improve, and keep reminding him / her everytime you find them slipping back into an abusive pattern. If they improve (because they truly value you), your friendship can live. If not, well... can you really call this person a friend?
If it's an unavoidable / blood relationship like a parent / grown up child... counseling is the the best option. Otherwise, keep your distance without breaking off. Dont be around them. Love them, but from a GOOD distance.
If its an outsider who you dont hold dear, but who has a significant influence in your life... an oppressive boss, insensitive teacher, bitchy colleague... the best thing to do, if you cant bear the abuse, would be to change your job / school etc... you cant take them for counseling!
Remember, you are a GREAT person. You are not here on this earth to suffer abuse at the hands of another. Your life is not so much affected by what's happening around you, but more so by how YOU CHOOSE TO REACT to what's happening around you. You have to ACT. There is always "another option". Work towards finding it and making it happen.
I hope this helped you... I've been thru abuse... and believe me, it sucks. I got out of it, it was extremely painful leaving my fiance... but i survived.
Good luck, and take care... May God bless you.