If you were living with your partner when your jobseeker's allowance means test was carried out (and their wages were assessed) then your payment should continue as before.
If you weren't living with your partner when your means test was carried out, your claim will have to be reviewed, and your partner's income will be assessed against you.
You will not be eligible for Mortgage Interest Supplement because you purchased the house while unemployed, and because your partner is in full-time employment.