How do I deal (much older guy/younger girl situation)?

There’s this guy that I’ve liked for a while. He’s been great. We’re really good friends. He always refers to me as his “best friend.” He’s very genuine, and he always stays way later than his workday (3:30 is his end time, 6-7 is usually how long he stays with me). He’ll usually spend 4 hours with me each day. He talks to me about his life, what he has to deal with at work, and anything and everything in between. That is, until I found out about his wife and kids about a week ago. He doesn’t talk about them much unless I prompt him. I previously thought maybe I should ask him out despite the age difference, but now that I know about his family, I would absolutely never. It just seems really odd to me. Any takes? I feel like I should start distancing myself, even if we work together.

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2 mo
I told him that I would be coming to this office less, and he was pretty sad about it. He asked what he could do to make me stay, but I said that there wasn’t anything he could do. For some background, my job requires a lot of travel and going between offices, and his doesn’t. I made the decision to distance myself a bit. He’s still been doing the same stuff and more, including visiting me for hours. It feels weird. He told me recently he doesn’t tell his wife about me at all.
How do I deal (much older guy/younger girl situation)?
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