SurvivingInfidelity.com^®

So I've got a problem and I don't know what to do.
My GF of 17 years is, at the very least, talking to and spending time with another guy behind my back and I'm very worried it could be more.
I've never been worried about something like this before in the whole 17 years of our relationship. She's always been very passionately in love with me and usually can't stand being apart for me from too long. She's always been a very social person, but not flirtatious and, above all, she's never been in any way secretive about the people she associates with.
Our relationship went through some problems over the past few years when she developed a heavy drinking problem. Things were very bad for a while, and I had to threaten to end things, but she got sober earlier this year and things really started to improve for a while. It's worth noting that, even while she was drinking, I never suspected infedility for a few reasons, but mostly because she was never dishonest about who she was with and where she was.
That all changed a couple of days ago. She relapsed in her drinking over the holidays, and I went through her text messages to try to get some more info about the extent of the problem. Instead, I found a long text message thread with some guy I've never met or heard of. Apparently they met at a bar near us a few months ago (it also appears her relapse has been happening longer than I thought). The texts start out fairly normal - it was nice to meet you kind of stuff before progressing "omg it was so good talking to you last night" and "I can't wait to see you again" type of stuff. Then he sends one asking her if they can hang out "somewhere besides the bar" to which she replies "sounds like a plan".
Now, let me say up front that there's no kind of "proof" they did anything physical, and it's even possible they haven't yet (although I'm very worried). But there are texts where they're planning to meet up and do things and even texts about her going to his house to have dinner and even sleep there (just saying things like "I'm sorry I woke you up with my snoring", but still). And the kicker - there's a text about her going over to his house to hang out the day after Christmas, when I thought she drove to the suburbs to visit her mom and slept there.
There's also frequent half hour long phone calls between them and messages from her like "can't wait to talk to you", "you looked so handsome last night" "you should come hang out with me I look great right now" and even a late night drunk text asking if she can "come see you right now" (which he didn't answer, and she apologized to him the next day for drunk dialing him).
I have no idea what to do. On one hand I don't actually know for sure if this is a physical affair yet or just an emotional one at this point. I don't have any proof of anything that she couldn't easily deny or minimize and I came about it in a somewhat unethical way (by going through her text messages, which I acknowledge I shouldn't have been doing in the first place). I also feel like confronting her with it will just teach her to make sure she deletes anything she doesn't want me to see in the future. On the other hand - I wasn't born yesterday. I know that there is something serious going on, but I don't know just how bad. I know I have to do something, I just have no idea what. I've never been in a situation anything like this before. This has all struck me out of nowhere and I feel like I'm still in somewhat of a state of shock. Any advice anyone can give me would be greatly appreciated.

Drinking is a highway to cheating. They all like to hang out together and things happen. She needs to get into treatment asap.

I am sorry you are facing this situation at the start of the year and throughout the holiday season.

But let’s be clear. She is cheating. She is lying to you and being dishonest and whether it’s a physical thing or not, she is cheating.

Coupled with a relapse from sobriety and you have a number of serious issues to deal with right now.

You may want to consider getting some professional counseling for yourself before confronting her. It may help you understand your feelings and help you make decisions on next steps.

You may want to keep a copy of their texts and how often they speak. This will help you avoid her trying to gaslight you and having to listen to the "it’s not what it seems" nonsense.

Be prepared for her trying to blame you for her choice to cheat. As in "you worked too much" or "you weren’t there for me" type crap.

It is only the fault of the cheater for the affair. There is no reason or excuse to why she cheated other than "she made the choice to cheat". Period. You could be the worst person on the earth, and it’s not an excuse or reason to cheat.

Continue to post here as you will get excellent t advice.

Sorry that you found us here. If you are in a serious monogamous relationship (which from your description you are), then I think you deserve transparency in this situation. You could casually mention that a friend of yours saw her with a guy at the bar and you never heard her mentioning it and whether she has something to say, because you think neither of you should hang out one on one with someone of the opposite sex. Then see how she responds. Whether she lies about it or confess and come clean with how far they have been. I hope it turns out that he is just an old friend but you have to prepare for the worst. So sorry your new year starts with this heart wrenching situation.

Thanks so much for replying so fast. And yes I agree with you - if there was nothing to hide she wouldn't be doing it in secret.
I think the most helpful thing I've seen you and others say here is to take a little time to consider what to do. I think I was taken back by the shock of the whole thing and really fretting over the "what should I do" part. Like I said I know I have to do something, I just don't know what - but it's giving me some relief to know I have some time to figure it out. And thankfully I already have a counselor, who I will definitely be discussing this issue with when I see him.
It's definitely also good that I seem to have found some experienced people to help me figure out what that "what" is.

Im sorry you are having to go through this nightmare. Keep posting, you will get some really good advice on these forums.

One part of your post stood out to me:

even texts about her going to his house to have dinner and even sleep there (just saying things like "I'm sorry I woke you up with my snoring", but still). And the kicker - there's a text about her going over to his house to hang out the day after Christmas, when I thought she drove to the suburbs to visit her mom and slept there.

It sounds like she has stayed the night over at his house. Im sorry to tell you this but if that's true the chances it went physical are very high. Get yourself tested for STDs ASAP, and find a reason to hold off on sex until you have more information.

Read up in the library here for lots of good advice.

I think you have enough to confront her now... hiding a relationship with another man, spending the night etc is an affair. If she has not had sex yet, you might stop that by confronting asap. The majority odds say she has slept with him already, why else do you spend the night with a man? But she will likely deny that when you confront. Most people lie about their affairs and give you trickle truth over days, weeks or months.

Dont rugsweep this! Take action, confront her and get out of infidelity.