As things are your ex can sell the house and leave you to whistle. However, from what you say you have a valid claim for an equitable share of the proceeds and you must formalise your claim and make it known by registering a Caution at the Land Registry. This blocks your ex from completing a sale until your claim is settled - very important for you. You could do it yourself only if you understand legals because sometimes complicated questions are raised by the LR. You will be safer doing it through a solicitor - cost to enter the Caution �100-�150 - and should your ex try to sell the solicitor will be the best person to fight your corner. Should you wish to move out your claim can be quantified and the Caution is still effective so that you must be paid when the house is sold. Often the entering of a Caution starts people talking sensibly again and a way is often found where one is paid off leaving the whole property with the other.