Fiancé’s suspicious friend

Me and my fiancé have been together for 4 years. We have a child who is 2. The first year he cheated an excessive amount. Since then he hasn’t done anything and I have regained my trust in him. Although he has a friend that I knew when I had worked with both of them. We will just call her Hannah.

Hannah met my fiancé, Jeff, about 3 years ago and they have been friends for 2 years. About a year ago Hannah got married and got promoted in so she has now moved up and out of the location where my fiancé works. The 4 of us have just recently started spending time together. The first time there was nothing irregular. My fiancé even at the end of the night asked me to make sure I was comfortable with their friendship, which I was so I said yes. Then, on his birthday, they came over again and she got drunk as did all of us but she was completely wasted. That night she spent the whole night trying to convince me that nothing was going on between her and Jeff and then she started holding his hands for a few minutes at one point and by the time I had seen she stepped out and went to the bathroom. Later on that night when they were leaving she had grabbed his hands and kissed one of them and told him goodbye and yelled “I love y’all” as she walked out. I didn’t really understand why she had done it or if her husband had been okay with the way that she had been acting towards my SO. After they left I had a talk with Jeff about it because it was behavior I had never seen between them before this and told him I was uncomfortable about it. I did tell him that I wasn’t asking him or telling him to stop being friends with her. I was just really uncomfortable with the way she was acting and that I had to say something to him about her actions for him to say something to her. He then told me that the kissing thing was weird but mentioned nothing about the hand holding and told me that neither thing would happen again and we went to sleep. I still feel very uneasy about it and do not trust her. I completely believe that he doesn’t have feelings for her but I think she does. Advice?