@FOUND SOUL,
I'll second Found Soul, but I'll add a few things:
- if who he is, results in you not liking who you become around him, and the dislike of yourself is becoming worse & worse...run. Staying is a long slippery slide down into an abyss of self loathing.
- If he is unwilling to change, and the second part of the above holds true...run. For the same reasons
- if you find your behaviour worsening, with no end in sight. Run.
- if you recall how you felt about yourself before you met him, and track how you feel about yourself over the time you've been with him...and it's a slow slide downhill, with no end in sight - Run.
- I think you get the picture.
Wherever possible (if you're looking for a long term relationship), find someone who enhances your self esteem.