Boyfriend says if I dont change he wld leave me and be with someone else?

That's crazy. I often ask people in relationships with common relationship problems "what is it that you think attracted them to you in the first place?"... Most people either draw a blank or give a not so well thought out answer. I mean if the question can get you to seriously thinking about how you all fell in love or got together in the first place, you'll probably know what he likes best about you with him even having to tell you. Although it wouldn't hurt to hear it sometimes. Ya know. But um good luck with that.