Should I trust my boyfriend again? He really hurt me, but it seems like....he changed?

Guys like that rarely change. Unlike movies a guy will not change over night, if ever. A male acting like this, spreading rumors about his gf's best friend and dumping the gf to have , doesn't even deserve to be called a man, that is the way a child would act if someone got on his nerves a little bit, spreading rumors, or wanted to play with a toy that another kid has, do I need to explain that one. This kid sounds like a jerk. Don't trust him, leave him behind, and reveal how much of a little kid he truly is. You got to look deeper than just what he shows you, I.E. humor, and the outer looks, you have to look at his true person and decided if that person is the one you like or the funny good looking shell. I hope you the best of luck and stay strong.