Ok firstly if you own the property jointly & so the mortgage is in joint names then you have joint and severable liability for the full debt so any missed, late or incomplete payments will reflect on your credit file as well as the wife’s. It’s not enough for you to just offer to pay your half in the cases i have dealt with over the last 15 years.
Secondly did you notify the lender that you were not living at the property? If not then how could they have known that you weren’t getting the late payment notices & court summons? It is your responsibility to keep the lender informed of any changes in who is living in the property. Sorry if that sounds a bit harsh.
Get a solicitor who specialises in divorce, see if you are able to get legal aid and ask the lender for copies of ALL correspondence sent to the house from the point you moved out so you have records of what happened & when. Keep copies of your bank statements showing the payments you were making in to the account the mortgage was coming out of.
In short unless the property is sold, the ex buys you out or you buy her out, assuming she or you can raise finance which is unlikely even with the current lender given the missed mortgage payments, I can see no way you would be able to get your name off of the mortgage. When someone’s name is taken off a mortgage the lender will always have to asses the circumstances of the person left on it to ensure it is affordable etc.
That’s what i would tell any of my clients if they were in a similar situation to yourself.
Good luck.