How do you find out if someone is married?

[MarjorieProops]

Hi I have been meeting a man I met on online dating for a couple of months. I have my suspicions he is married or with a partner. The following things make me think this:

1. He only meets me once a week. Never at weekend and if so only on Sunday night. To be fair he lives 40 miles away though.
2. I have not been to his house. He says he lives with flat mates and they have issues. He says I could stay when they move out soon.
3. He texts in morning and last thing at night, during day but not a lot as I think he works very hard.

It may just be the way he is, but I would like to find out. I have googled and can't see anything. Sometimes I think he isn't taken and then I think he is. I just want a way of being sure. Sounds silly but any suggestions?

I think dating around too.

I have been silly and gullible, probably should have held back.