Not on deed or mortgage

My soon to be ex bought the home prior to marriage. I have been living it in and making the mortgage payments since he walked out. I had planned on trying to assume the mortgage and stay in the home, but I did my research and the home is upside down by 35k (mortgage balance vs appraisal). I am not on the deed nor on the mortgage - can I walk away from this without legal ramifications?

So long as you are not a obligor on the mortgage, you have no obligation on the loan. I would give your spouse notice that you intend to vacate and will not be paying the mortgage moving forward.