I have been in a serious relationship with my girlfriend for over 8 years.  We have a two year old daughter.  Earlier in our relationship (maybe 2-3 years in), I came across some Facebook interactions she had been having with one particular co-worker that made me uncomfortable.  These were not secret messages or anything - they were public comments viewable by anyone who was a friend, so there was no attempt to hide these from me (at least not deliberately).  These interactions were still highly inappropriate I felt, and when I told her they made me uncomfortable, she seemed to agree that they were inappropriate and to be deeply sorry and said she would just stop responding to his comments.  I have never been the jealous type, but this one guy always rubbed me the wrong way because of this, and she knew that. 

For the past few years, I have noticed that she seems to be checked out of the relationship.  Whenever I confront her about it, she always reassures me that she still loves me, and I would always say something along the lines of, "I need to act like it; not just tell me".  And for the next 24 hours, things would be OK, then it would be back to checked out status.  About a month ago, while she was showing me a video on her phone of our daughter, a text from the co-worker from her Facebook interactions came through, and she quickly hid the notification.  She knew I saw it, and said something like, "what does this dufus want?".  I let it go for the moment, but it ate at me all night, so the next morning I asked what it was about, and she said it was about work, but couldn't be specific about exactly what the text said....because she deleted it.  I asked why she would delete it, and she said because it's a conversation she doesn't want to clutter her phone, but they only text about work.  I asked that if all the texts are always about work, then why would she act as though she had no idea why he was texting.  This seemed like a contradiction to me.  I didn't even know they had exchanged numbers, and text fairly frequently.  When I asked about other conversations in her phone, I realized that she is only deleting his texts, and she said it's because she knows I would be upset.  So, her explanation changed from "to clean up clutter" to "I knew it would upset you".  I also asked why they would need to text when they both have perfectly functioning emails, and she says it is because he doesn't answer his email.....but according to her - he is always the one texting her, and she responds.  Something isn't adding up. 

Outside of the flirtatious messages on Facebook, this girl has given me no reason to distrust her.  We had a talk and since then our relationship has been great.  For the last month, we touch a lot, we have been intimate alot, but something still seemed off.  I just went back to those old Facebook interactions and found a lot more than I had originally seen.  An actual obscene amount of them, and the vast majority of them highly inappropriate - to the point where we both acknowledge that she had an emotional affair with this guy for about 2 and a half years without me knowing about it until a month ago.  She has insisted that she loves me and wants to spend the rest of her life with me.  She says these things, but she hasn't actually DONE anything.  She says they hardly see each other at work, and when they do, they don't speak.  Yet, he recently commented on a photo from our daughter's second birthday as if he knew her (he knew her nickname that only we use).  I asked how he would know, and she simply has no answer.  I don't think she is physically cheating on me, but I think she is being dishonest about the extent of her relationship with him, and I have told her repeatedly that I just need her to be honest.  She has said that he grosses her out and makes her uncomfortable, but she doesn't actually ACT like it.  It's as if she is downplaying her relationship with him (one that could be completely innocent) for my benefit, and that's not what I want.  I just want honesty.

When you put it all together, it has all the hallmarks of someone who is straying.  She had an emotional affair with a co-worker for 2-3 years without my knowledge, and when I expressed that I was uncomfortable with what at the time was just the tip of the iceberg, she said she would stop (she didn't).  She then deleted text messages from the guy she knew I had a problem with for 4-5 years until I finally saw one.  She was distant up until I saw that text despite me constantly telling her I needed her to start acting like she wanted to be in this relationship.  And now she suddenly decides to start acting like she is in this relationship. 

She claims she will do anything to show me there is nothing going on, but so far - SAYING that is really all she has done.  I keep waiting on her to decide to just remove him as a friend on Facebook.  I would think this would cross her mind if he makes her as uncomfortable as she claims, but he is still there.  I know I'm kind of all over the place here, but I just don't know what to think.  I have been cheated on in the past (in a terrible relationship), and I am hoping that I am just being a little paranoid about it.  I would just like an outside perspective.  I plan to propose to her soon, and she knows it is coming as well.  I believe her when she says she wants nothing more than to marry me, but I also don't want to get burned.

Hey my man,

I have been where you are. Its the worse feeling. Its overwhelming. Its on your mind 90% of the time. As you point out, you don't believe she is physically cheating on you, but she clearly isn't being honest with you either. And that lack of honesty is what is causing your strong anxiety about her and your future.

Please let me give you this advice, it cannot continue. For your own sanity do not let it carry on. It has to come to a head, even if one of the possible outcomes is a painful one. Trust me on this, in time you will see you made the right decision.

You really only have 2 options. Be deceitful, and carry out espionage on all her social media/phone interactions with him. Do NOT let on to her that you are doing this and that anything is wrong. Reassure her things are good while you do this. There are ways you can google for yourself to carry out this kind of exercise. I did it. And I found what I did not want to see. It broke me, but at least I knew. I took her out for a meal, a public place. And calmly told her exactly what I had done, and found out. And that I was leaving her. She cried. I got upset she was upset, I still loved her. But I found the strength to get up an walk out. The toughest thing I have ever done, and looking back, the best thing I ever did.

If you don't want to be so extreme, lay it all out on the line. Tell her in no uncertain terms that her behaviour and secrecy is completely unacceptable. And you won't put up with it. Have an overnight bag packed, so she knows you mean business. And even leave for a night or 2 if you feel you have too. She needs to understand that her respect for you as her lover is paramount, and completely overides the working relationship she has with her collegue, innocent or not, considering her past behaviour with him.

Do not propose until this is straightened out. And please don't let fear win out, your sanity won't take it. Be strong my friend, and best of luck!