How do we get through the fact my husband fathered a child before we were married but were in a relationship?

i have been with my now husband for 9 years, 2 years into our reationship his son who was 3 at the time came to live with us as his mother didn't want the resposibilty. a year later we got married and tried to have a ababy of our own which resulted in an eptopic pregnacy, a year after that i had a cyst on my ovary.removed along with an ovary which meant we had to go through ivf which wasnt succsessful. anyway there has never been an issue with trust i truelly believed my husband loved/loves me. about 2 weeks ago a women sent me a message saying that she had a 6 yr old son to my husband . the truth came out from my husband that he had a dna test taken when the child was born and has been giving her money for the child up until 2 years ago. the dna test apparently was never proven because the mother never provided the child sample..my husband is a really good dad to his son so he would never deny his child, he says he genuinly never thought the child was his he was just giving her money coz she was threatning to tell me.he has nver met the child. at the moment i dont feel angry or anything to be honest.....i;m worried that this isnt normal and now not only do i have to deal with the fact he cheated i also have to deal with the fact this women has the upperhand in our lives now with regards to financial issues. i love my husband so much but dont know how we are going to deal with this also aswell i know when this sinks in the fact that i have been through so much heartache to have a baby with my husband will make things even worse