So, DH and I have been married many years, 2 kids. We went through a bad patch a few years ago - he more or less moved out, we ended up going to counselling which got things back to being fairly amicable but not more than that, and he moved back in but has been in the spare bedroom ever since, partly due to snoring but he's resisted any suggestion that he move back into our shared room and I haven't pushed it. We both work long hours and are tired. He's very attached to the kids, who are teens, and though we have talked about splitting up he says he doesn't want to. Those conversations usually take place after big arguments about something, he gets very angry and says I have to be the one to leave the house if we split up and he won't let me have the kids etc. There is no physical affection between us at all any more.
About 9 months ago he started having to attend work events in the evening, practically every week and sometimes twice a week, which he has never done in all the time I've known him, and he's always had same kind of job and worked for same organisation. If he's not at an event, he's often working late. I work late myself several times a week, so those days he's home 'early' (7:30 PM), but then I work from home the other days.
More recently he's started, several times a week, having to 'pop up to London' for supposed late afternoon meetings or evening events. Again as his work is firmly situated in our own city which is about an hour away from London, this seemed strange, and I have commented on it and queried it a few times but was always brushed off and told that I am in no position to criticise as I work long hours too, and travel. He works very close to our home normally, no real commute to speak of. He is a real workaholic though so, maybe plausible.
Today he left his phone on the dining table while he was doing something in the garden. He never normally leaves it around and I don't have the password. It happened that it was still 'unlocked' and the screen was showing the recent calls, and I saw 3 calls in close succession this morning from the same unknown mobile number. Thought that was a bit weird - why is he getting random mobile calls on a Sunday morning - and then scrolled down to discover several recent calls from a woman who works at the same company as him - listed under her name as she's in his contact list - who I've suspected he was involved with in the past. I don't know her other than by sight, but I have seen them interact at a couple of company events over the years and immediately thought there was something strange going on. However she was working in another country, or so I thought, so I haven't even thought about her in quite a while.
Thanks to Google I've now found out she's actually working in London now. She does a similar job to him so there could possibly be an innocent reason for them to be in touch, but given all the other factors I think it's more likely than not that something's going on. She is single, no family, very attractive.
The question is - how do I find out for sure, and get enough proof here that he can't deny it, if something actually is going on. He will never in a million years admit anything just from me asking him. I tried to get a better look at the phone again tonight by asking him to show me something random on it, but he just hovered over and took it back, was obviously nervous. I don't think I'm just imagining this, I've known him for a long time. What do you do in this situation? I don't know enough about his schedule to try to track him physically and it seems like an insane and horrible thing to do anyway, but maybe there's no alternative? I also work full time so not in a position to take lots of time off midday to shadow him, nor in the evening as someone needs to be home with the kids if he's out - and I wouldn't even know where to go. I'm thinking of trying to call the random mobile number that was on his phone this morning just to see who picks up.
Really feeling miserable about this and of course hoping it's not true but pretty sure it is. Better to know, and take some action to make sure the kids and I are financially protected and that I can move forward somehow, than just to keep going along head in the sand. Older child is about to take GCSEs so can't risk a big blow-out right this minute, in any case. We are supposed to be planning family summer holiday tonight :-(
Appreciate any advice.