I'm thinking of leaving him coz I'm not happy....?

Maybe you try to tell him how you feel. If that doesn't work than think of this, my mother use to say this messages to me. The first one was there are a million of fish in the sea, therefore you're bound to bump into many others. Also, One man's trash is another's treasure! Just stay positve and the only important is that U're HAPPY. That is all! Good luck!