Chasing mortgage arrears

helpneededurgently

Hello. Can anyone help. My ex-husband and I when we sold our house down south over 20 years ago ended up with negative equity. This was with mortgage express. With all the fees and interest added on this was approx. £47K. We were paying back approx. £85 per month. In 2008 my ex-husband left and just disappeared (he was actually registered as a missing person!). I could not afford my current mortgage payments let alone the arrears on the mortgage express one. I went to Citizens Advice and they organised a deal with Mortgage Express where I was paying £1 a month. THis has continued until now. I am now re-married and have received a letter from Mortgage Express via NRAM trying to trace me. What should I do? I have always wanted to clear this debt but have been physically unable. I have operations on my knee and foot and struggle to work. Should I get in touch with them and confirm where I live and my new name. If so can they ask for more money and can they ask my husband for money? May it be possible to come to an agreement? I understand that when the CAB arrangement was made they split the debt in half. I have no idea if my ex-husband has become bankrupt or has even been paying?
HELP WHAT SHOULD I DO??