Long term partner moved out

Hi all, my partner has moved out and I have used the 5 minute benefit checker on mse to see if I'm entitled to anything. Everything looked OK until I got to the bit about a second property and now I think I may not be entitled to much because my name is on a mortgage for another property. To cut a long story short I have a 5yr mortgage on the property I live in now and also a long term one on a house that is in neg equity, that we've tried to sell but had no luck.

My question is, will this second property affect any claim for benefit? (the house is worth about £80k (could be less), we paid £115K for it and we owe just over £100K to the mortgage company).

Thanks in advance