Common property problems, need help.?

My father-in-law bought a house in his name, second name being that of my husband. Half the cost of the house was paid by my FIL, for the remaining half my brother-in-law took a loan, and the loan installments are being paid by my husband (he gives the installment amt. to my BIL). Its been only 1 year that we are married. My BIL got married only recently. Since marriage, he and his wife are staying in our house, making it difficult for us to stay in (it being 1BHK flat). My BIL has 2 other flats of his own, but he does not go there. I am feeling really irritated and mad, since our bedroom has been given to the new couple. We have booked a flat for ourselves seperately, but we havent got its possession, it may take another 6 months or so. Also, I am 3 months pregnant, I need a seperate room for myself. What do I do?