Is this all just friendly, or am I being paranoid?

I am figuring it out, yes. The issue I have is that the place where I work is stressful and lacks management support. I have two to three colleagues, including him, who are my sounding board. I wouldn’t want to lose that support by shutting him down.

That’s a good point.

I am not much younger than him. Our kids are of the same age.

OP it's ok for like minded people to be friends at work, in a supportive way. I'd make it clear now to him, obliquely, that you never go out with married men.

Good look.

Do you think he's being paternal/avuncular given that you are younger?

It’s so hard to say because, as women, we’re so used to men having ulterior motives for being friendly! I think my deal-breaker would be “would he say that to me in front of his wife?” and if the answer is ever no then I’d back off.

I have a great relationship with my old manager, he’s a wonderful mentor and we continued this mentor/mentee relationship after we both left the company and he supported me through leaving a very toxic work situation. It has never ever been more than a respectful friendship, though of course there were rumours, toxic workplace boss also accused me of sleeping my way up the ladder. My old boss/mentor did happen to mention that he also went through a rough work transition when he was younger, so he understood the pain of it. There are genuine people out there who only want the best for you! Friendship and the satisfaction of helping someone succeed I believe are their own reward.

The one about the work trip?

yup. Wise.

I was having similar thoughts op.

A few of your posts come across as though you are hoping we see something in it all - especially as it isn’t really that tricky to shut someone down. “ I’d better get on with my work now” when he’s getting into personal information is all it would take to clear the situation up tidily.

“ I’d better get on with my work now …”

You are his work wife. Sounds like he is infatuated with you.

I say ride it out until you know for sure one way or another which way the wind blows. Maybe he likes hanging with you because you make him feel young, maybe to him you two just click, or maybe he’s bisexual and has the hots for you. There’s a good chance the first two options are correct. Why ruin a friendship on a maybe?

My female colleague told me yesterday that I am so tall and beautiful and asked why I am always conservatively dressed. She said that I should be wearing something a bit more fun and stop dressing like a nun.

Oh please. This is so fake.

OP he is not doing this innocently. Gosh I've been there soon many times from men that I though as a mentor, fatherly figures, from married colleagues that I felt safe with because they were always talking about their wife (an strategy to get into intimate conversations and intimacy for most men leads to sex) If you are single you will very likely get blamed if his wife's suspects anything and this may damage your image work. Distance yourself

I had a male colleague who was the best person I have ever worked with- we got on well, had similar sense of humour and would always encourage the other to be the best they could. Never anything other than a supportive working relationship- did not contact each other outside of work but we worked well together and were closer than to some of our other colleagues because of similar work ethics/wanting to do a good job. Nothing romantic and although I was gutted when he left, we did not keep in touch. You have mentioned this man does not contact you outside of work, you feel he does not make inappropriate comments and is supportive and encouraging. In my experience, irrelevant of gender, two colleagues appearing closer will lead to comments from other staff members.
I think if it makes you feel uncomfortable, then maybe taking a step back. I do think your concerns may be shaped by previous experiences of male colleagues- perhaps as my own has been!

It sounds like he is playing the long game and if you were to give him the hint of a chance, he'd snatch it up. I think that married men are often like this because they don't want to blow up their comfortable home life if you aren't a sure thing.
I know how it feels OP, it feels like they all hit on you eventually. Even my gay best friend from school did it.

I work in finance and have had quite a few genuinely close friendships with male colleagues over the years that are quite different from their relationships with other colleagues - probably linked to me being a woman and the rest being male as I do think men often communicate differently with women and I like building authentic relationships. However, not one of them has ever been even slightly inappropriate. I would never jump to the conclusion that just because they show an interest in you as a human being and genuinely care about you it is somehow sexual - indeed in one of the few cases where I got comments about how it must be more from others I was sure it wasn’t and later found out he was privately gay. Don’t deprive yourself of a great friendship just because a bunch of people on mumsnet still think no married man should have female friends - if he’s never said anything that is inappropriate (being glad you’re happy is not inappropriate) then trust your instincts.

I agree with this. 100% he fancies you but that doesn't mean he'll definitely over step. If you made the first move though I doubt he'd say no.

If I were you I would make it really clear to him where I stand " It's wonderful to have a nice work friend like you, I just told DH the other day. Maybe we could all go out to dinner with spouses an evening. I would love to meet your wife."

Would you feel uneasy if a woman was treating you this way?
I don't click with many people but the ones I do click with I become very close to, male or female. I've had a male friend of 20 years who knows all my secrets and we know each other inside out. Nothing romantic ever. I also have had a male colleague who was the person I'd usually go to when struggling at work and we also discussed personal things. Never had any contact outside of work, both happily married and never anything more than very good work friends.
If it's been like this for a couple of years and he has never come on to you or tried to contact you outside of work why are you now questioning the relationship?

this!

If he were a she would you be asking the same question? I get why you are though. It’s a shame that we have to question these things because of that reason.

I am close with a few men at my work, we laugh and joke together, take walks to the shop together on lunch, go for dinner when working away together, all completely normal behavior where i have worked. If he's not making you feel uncomfortable I don't see the issue. If he is, ask him to stop or distance yourself

Sounds like he respects you, likes working with you and wants you to be happy. Nice.

I'd leave it, I'd continue to work well together and ignore him out of work. I wish all my colleague were like this