No privacy

My fiancee, our child, and I had to move in with her mom. In which her sister and disabled brother also live in. Her mother is very demanding, loud, rude, and hateful. But means well. Our child is picking up on the bad habits. We are trying to get enough funds to get out, but for 4 months we have not been able to have any privacy. We are both sex deprived and can't do anything about it. Any suggestions? Any type of cheating is not an option.