Thanks to everyone that has responded so far, I really appreciate this. As I type this I'm getting the locks changed in the house (I don't live in the U.S. and if he complains then I can fix the problem by giving him keys). Given that as far as I can tell he hasn't been back to the house in 9 days I'm not too worried about this change.
After typing the post above I went to work and it finally hit me that the ex-friend (although I hesitate to call her that as she wasn't really a friend) is most likely the ow even if only as an emotional affair. At the very least he lied to me about keeping in contact with her and that's not ok. I also think he might be staying at her house (no concrete proof though). Otherwise the rest of his friends are mutual friends, mostly married that would try to talk some sense into him.
I got to work and talking to one of my friends there and was feeling sorry for myself because I thought that everyone would look at me strangely when they found out about ow and H at ow's party on Saturday. My friend believes that this won't be the case. After having a bit of a cry I got on with my day which luckily had 2 long meetings. The meetings went well so that boosted my confidence a bit. When I got back to my desk (I made a deliberate choice to not bring my personal phone with me to the meetings to avoid the obsessive checking), I had a text message from H. He asked about the cat (my kitty is being treated for lymphoma and is doing well) and told me he had a counselling session. I haven't responded yet and was hoping to get some advice from experienced people on what to do. This is the first contact since he left 9 days ago. Should I offer to go to counselling with him? Acknowledge the text?
What he doesn't realise about ow / ex-friend is that she is only using him to get back at me. She couldn't destroy me personally or career-wise so she decided to take advantage of him. She couldn't care less about him or his feelings.
I also saw from the joint credit card (luckily with a low limit of 2,000) that he's bought a plane ticket. I have no idea for when or where but from the cost it's most likely a domestic flight to see his family.
My goal in all of this is to remain calm (for me and for my kitty) and not make any decisions in the grip of a strong emotion. I'm not religious but I like the expression "let go and let God" that I read either somewhere here or on another webpage. I want to try to stay as rational as possible given that he's acting like a spoiled teenager.
What is very, very ironic is that his brother in law walked out on his sister a few years ago. His sister was a few months pregnant at the time. They divorced and he went to live with ow.
Again, thank you to all who have listened and taken the time to post. I am grateful that in your pain and confusion you can reach out to a total stranger. There's so much information in the posts above that it may take me a few reads to absorb all the information.
