Separated and not paying my half of the mortgage

After living apart for 18 months I have decided i want a divorce. My husband and I jointly own the house (mortgaged with Caja de Canarias). If i stop paying my half, what position does this put me in legally when i eventually start divorce proceedings. I dont want the house, my husband doesnt want to hand it back the bank with fear of the debt we may acrue, but he doesnt want to take my name off the deeds either. What can I do? I feel trapped mainly because if we maintain this house 50/50 as a divorced couple i will have to live here, but i cant have my ex hubby turning up demanding to stay here when it suits him cos 50% of the house will be his, and should i start a new relationship how would this affect my rights to have him move in?. Please help. x