I was married for 14 years. We split up for a while and she bought a house in her sole name. When we got back together I paid the mortgage since she was at college. However we’ve now been divorced for three years and she has moved her boyfriend in. She says I’ve no claim on the house since my name is not on the deeds and there’s no proof I paid for anything.
You should see a solicitor immediately and register a claim on the property. Although you are divorced you evidently haven’t reached a financial settlement with your ex-wife. Even if you hadn’t contributed to the mortgage you would still have a claim against her, but the fact that you did will enhance your claim. Since you were married the fact that your name isn’t on the title deeds is really neither here nor there.