I admire your persistence and grit for each other in this relationship. But not much will move you forward as a couple until he moves out. At your ages it is time to carve out the kind of life you are looking to live independent of his family. They sound abusive, demeaning, and unsupportive. The question for you is whether or not this relationship works for you. If you move in together it is likely they family will not accept you as you move forward.
The work for your boyfriend is to make the break independently from his relationship to you. He would need to leave because of issues with the family — not only because he loves you. This is difficult but likely to be a needed step. If he leaves only for you they will blame the relationship (and you). If he leaves because they are not honoring him it will be understood differently. It is an act of independence rather than because of his feelings for you.
I highly recommend you find counseling through your university for yourself as you work things through with him. If it is possible for the two of you to see a counselor together this will be important. It will help clarify what needs to be done as a couple, and what needs to be done independently.
Wishing you patience and peace,
Proof Positive Blog @ PsychCentral