I had an affair with a married woman of 26 for two years when i was 54,she had 4 children?

her husband had a vasectomy 4 years prior to our affair, he was a friend of mine,one night when he was drunk he fell asleep and we had ,for two years we had at every opportunity,then she got pregnant and i finished it,that was twenty years ago,someone has recently been trying to find me and i found out it is this lady who has just told her husband, what do i do