Is a straight guy into me?

I sit next to a guy at work who’s older, married and straight and I’m gay. I’m not sure if he’s secretly closeted/curious, and holding this back, or if I’m just deluded.

This basically started where I’d been on holiday for a week, when I came back he was really happy to see me, when I didn’t really think he’d be like that, he’d never been overly cheery in that way before.
That eve I sent him a text about something we were talking about earlier in the day – no big deal just a general text, he replied and I didn’t send a reply to that as did it feel I needed to.
The next day he was waiting at the bus station to pick me up, saying he saw my bus come in. Then the next day after that he text me in the evening saying he hoped my meal out was good, as I told him I was going for food after work. He then told me about what he’d been doing that evening.
Since then he’s text me a few times, generally about work or sometimes about how he’d been out for a drink etc.

We then had a night out with work and during the night out he invited me to stay at his house, as I live pretty far out. Nothing happened and I met his wife in the morning, but after I’d got home he messaged to check I’d got back safely and talked about how I’ll probably stay round again in the future and we can plan things like breakfast and lunch better.

It all died down after this text wise, and I initiated them more from here as I missed the conversation. But at work he blows hot and cold with me, sometimes he’ll be physical and pat me on the shoulder when saying goodbye, or he’ll squeeze me on the shoulder as he walks past, then other days he’ll be quiet and quite blunt.
The next time I went on holiday he wasn’t working in the office and text me to say he hopes I have a good weekend, then when I was off sick from work a few weeks later he messaged me to say he hopes I feel better soon. He was also apparently asking about me everyday to my other work pals.

I feel deluded but then there’s just certain aspects the make me think there’s something there, even if it’s not a curious side? I just can’t imagine him considering me as a friend before all of this, and I’m not sure why he would.

He’s known for being flirty with women at work sometimes and he does talk about women, and I see him check them out.
There’s not many gay people in my office and they all act fairly alpha male, to the point where I just think ‘we get it, youre straight’ sort of thing.

Thoughts?