I (24f) caught my fiancé (27m) coming home from the neighbors (32f) house. How do I confront him?

Throwaway because my fiancé has a snooping habit and tends to get on my phone/computer without my knowledge or consent. <br><br>My fiancé and I purchased our first home together last year. We were so excited to start our new life in our own home. <br><br>Our neighbors are older than us but quite friendly. The female neighbor has two teenage boys and is always home on weekdays as she works from home. My fiancé has always spoken about how nice she is and how friendly she is to him whenever he is mowing the lawn or doing yard work outside. <br><br>We live in a culdasach so we all see each other quite frequently but we also respect each other’s space. So if someone is working in their yard everyone says their hellos but we all go about our day. <br><br>So yesterday I had the day off work but my fiancé didn’t. So I was driving home from getting some groceries and as I drove past our culdasach, I see my fiancé walking from our neighbors house. My heart instantly sank. <br><br>I drove up to our house, parked my car and pretended I wasn’t home yet. I could hear the tv in our living room turn on. I waited for about 10 minutes before walking in the house (just in case he got suspicious). <br><br>He was super nice and offered to carry my groceries inside. I thought to myself- ACT LIKE EVERYTHING IS FINE UNTIL YOU SEE THE RED FLAGS- <br><br>I didn’t notice anything off with him. He was his normal self. So after we put the groceries away I said I was going upstairs for a nap as I had a migraine. <br><br>I’ve been sitting in bed since I heard him leave for work this morning and I just can’t stop thinking of all the possibilities. <br><br>1. Is he having an affair? <br>2. Did they have a lunch together? But he was in work clothes and she was in her pyjamas- not to mention the time was too late for lunch (3.15pm) <br>3. Are they old friends? <br><br>He’s been acting completely normal. It’s honestly been killing me. I have no proof of anything happening but I know for a fact that nothing good can come from a man and a woman alone behind closed doors. <br><br>He’s been working normal hours lately so he’s usually off by 5-5.30pm- he will be home in the next few hours and I want to confront him. <br><br>What do I say to him? I don’t want him to know I saw him but I really think something is up. <br><br>I really want to bring the neighbors name up. But I don’t want to seem like I’m crazy.<br><br>Is there any way I can get to the bottom of this without him knowing I know more than I let on? <br><br>I just feel so horrible. I really thought we were happy together but now I’m starting to feel like I’m just a fool.