Me and my bf (always feel odd calling him that, I'm in my late 30's!) started as fb's and both realised we had feelings and we've been together now for several months.
He is a wonderful man, and I'm blissfully happy. Probably too blissfully 
When we met he had only recently separated from his wife (it wasn't an issue in the beginning as neither of us planned for this to be a relationship) and was still living in their home and she had moved back to her parents with their ds. This is what he told me anyway.
I've never been to his house because his ex lives around the corner and pops back now and again without warning and he doesn't want to upset her.
Their house is rented and his ex is staying at her parents and my bf is moving back to his parents for a while while he saves some money. Only this hasn't happened yet, I'm not sure on time frame.
I realise that much of what I have said is a red flag to him not being single at all, but he comes to me, sometimes last minute plans and stays the night, is not constantly checking his phone and when he's not here then we often text or speak on the phone at different times of the day. So in that respect, it doesn't concern me.
I just have a niggling doubt. To be honest I have fallen deeply in love with him, he makes me feel amazing in every possible way and he could not treat me better than he does.
I don't develop feelings easily, I don't let anyone in easily and I'm not usually a naive person but I would really appreciate peoples opinions.