why can't i leave him and should i leave or try harder?

25fuk

hi any one here?

Basically i have my own problems and don't feel like i am maturing well at the moment, my bf is a year younger than me and i totally understand he will be slighty less eager to grow up than me yet he is responsible enough.
He lives abroad from his family and i feel the pressure of him missing family life. His brother also lives with us as he has nowhere else. They're relationship is improving slowly as it was very volatile previously. These are not my problems but i feel them all the same.

In the past my bf has been very hard work, abusive, violent, possesive and everytime i have asked for space i do not get it. He ignores what i am saying as if it means nothing cause it does not fall in line with his benefits/wants.
He has been unfaithful and is addicted to porn. We have aired this on many occassions where i tell him how i think he prefers these girls on me, as he will not venture much in the bedroom. Yet i am satisfied with our sex life? I just wish he would spend his energies spicing it up for us and not him. I have oftened initiated underwear, handcuffs, toys and watching porn with him. But he still is not quite answering my needs.

I now feel like it is hard to be nice to him because this is how he switches it when i am upset. He blames it on me or makes me carry his guilt, and he wants me to be sweet with him but i am finding more and more difficult. I don't feel like he is the one for me to keep doing this yet i feel trapped by him. I even find it difficult to say i love you and he always has to get this out of me. Whats the best thing to do if i stay or leave?