Hi I just found out that my partner has been cheating with another women he's been on my morgsage since 2005 I put most of the money down to get this house can you tellhas he got tohave half my house or what please can you give me some advice

Not everyone here is a lawyer.
Where do you live, and what type of ownership is on the deed?
Please use the orange answer button.

ANY question on law needs to include your general locale as laws vary by area.

Being a signatory on a mortgage doesn't give someone any rights to the property. All it does it make them responsible for paying the loan. What conveys ownership rights to the property is being on the deed or title.

However, depending on your area, he may have rights to property acquired during the partnership. If he has contributed to the down payment or the mortgage payments, he may have some rights there as well.

I live in gwent and its joint ownership

Ugh... is Gwent located in Wales?

So if he's on the deed as joint owner, he owns a half interest in the property. Therefore, if you split he's entitled to half the value of the house.

Agree, being on the mortgage is not ownership, it is merely debt, who is on the deed and how they are listed. Also was there any written agreement as to dividing the property latter