We have all felt these feelings before, I am sure ... loneliness, wondering why there are those who feel nothing about being with a married person. It just sickens me.
It's up to you, of course, if you hire a PI. Depends on how much you want to know for sure. My H wasn't having a PA so all my proof came from the computer. You do know he has a secret phone, and that alone brings his fidelity into question.
I bet it was nice to have your H look you in the eye and tell you he loves you. Mine never really has done that ... usually over the phone, or as he's leaving on a trip.
It sounds like you are set if a bomb drops. There is a poster here that believes in bringing an A to the light. Sometimes, it's the sneaking around that makes it exciting, but once it is known by friends and family, then the fun is over.
So difficutl to know what to do. When I discovered my H's EA, I had all the proof I needed. Yours is a little iffy.
Take care.
Me:57 H:52 M:28 Got another lawyer last year and filed. D35,S/D twins28,D22 EA4/04 End? Who knows? "Life is like a mirror. Smile at it and it smiles back at you." — Peace Pilgrim