Welcome to SI. This place has helped me a lot even though i found it almost a year after I founf out. Got to the healing library they have good things to start off. Then get the book " just friends". My fWH swore up and down that it was just an EA until I found evidence months later.
Well I had it but was stupid or innocent because I trusted him. In February I found him looking for hotels.. He claims it was for us to get away on valentines.... I responded you were taking me to a variety of cheap motets near our house??? Ugh can you stay stupid. How didn't I see that.
Then months later I found a condom in my car. He said he gave it to DD as she was going to a party that weekend. I called him on it. Called DD asked her point blank and she couldn't stop laughing. My heart stopped beating. I knew then but chose not to believe it.
I was shocked but didn't think he had it in him to cheat. Anyway get yourself and she tested for stds. Tell her that it would make you feel better. I contracted several stds. For over a half year I didn't understand my symptoms. Thought they were from all the sex. Nope.. My fWH A was six months and they had sex within two weeks of meeting. WTF.
So honestly you need to be safe. 9 months is a long time not to get sexual. Sorry