Paying the mortgage after seperation

Hi,

I joint own a house with my ex. i have offered to indemnify him if i can live there (without him), but he has refused.

He has made it unbearable for me to live there so i rent somewhere else. What are my rights with regards to paying the mortgage currently i'm paying half and its a struggle as i have to pay rent too.

We did have a lodger but the same week he received a letter from my soliciotor saying my intensions to take on the mortgage by myself he turned on the lodger and evicted him.