Is this crossing the line or am I overreacting?

My boyfriend and I have been together 5 years. In many ways he is a perfect partner: extremely supportive, positive, thoughtful, makes me feel very loved. However, I'm having a dilemma. We share a computer right now (it's his desktop, my laptop is broken so he can knows I use it regularly) when I opened the browser today the first tab was his open FB and two conversations were up. Two conversations with two different women. One was an ex from about 10 (or more) years ago. They dated as teens, their families used to be close but have since fell distant. The other was a girl he works with.

He doesn't usually message other women often so I was pretty surprised to see these and I also couldn't help but notice BOTH conversations were plans to get drinks - separate occasions both one on one.

The ex I understand, they've known each other for most of their lives. To note: he contacted her and he suggested catching up update over drinks.

The colleague conversation made me really uncomfortable, she is blatantly flirting when him, constantly sending him suggestive jokes and winking at him. I looked at her profile and got the sense she is a pretty generally flirty person (tons of selfies, same rate of winks in picture comments, etc). This time she invited him out and he said yes but that he was in a relationship and therefore would go only if her intentions were platonic.

Fine. But he hasn't mentioned his plans to go out with either of these women! For me this doesn't feel right - am I overreacting? I already know what he would say about the coworker "she knows it's platonic, she invited me out several times, I've said no several times, I don't want to make our working relationship awkward. Why is it not okay if it's as friends?"

Honestly I would be fine if he were to spend time with either woman as long as he told me first! I know he's going to say he didn't want to worry me and since both women know he's in a relationship, what's the problem?

Is he trying to balance both relationships in a diplomatic way or is he being an ? Am in overreacting or is this a breach of trust?

I feel trapped now and that I can't bring it it up without being accused of snooping. Other than this I feel like our relationship is in a great place. Should I just look the other way and let this go if I really do trust him?

When a couple is discussing becoming exclusive, that's the time to bring up relationship boundaries to see if you are on the same page.

If you haven't had that discussion, now is the time to do that because both parties need to agree on rules or you both will be arguing with neither of you being happy with the situation.

If you're not compatible about the rules, you've made a mistake in the choice of your partner.

My husband and I don't give our numbers to opposite sex co-workers, etc. for the purpose of being in communication during leisure time, and we don't hang out with the opposite sex outside of family unless we do it together and/or in a group setting. We also don't stay in touch with exes. These are the rules we agree on.

Other couples might be fine with opposite sex friends. It's about whatever works or doesn't work for you. The fact he didn't mention any outings with his female "friends" speaks volumes. Keeping that info a secret is just as bad as lying. Apparently you've had some experience with his excuses. Doesn't want his co-worker relationship to be awkward? Give me a break. Women understand when a taken man can't meet one-on-one with her. And if they don't get it, who cares? Obviously, he doesn't care that he's putting his relationship with you in jeopardy.

Take your rose colored glasses off and maybe you will see he finds excitement by meeting up with other women without you present or even knowing what he's up to. He's playing with fire and you're trying to cling to the fantasy of who he is rather than the reality of who he really is.

I recently had a somewhat similar conversation with my man regarding boundaries. My BF is very charismatic, charming, handsome...just a great guy. BUT...I do feel that what he views as "being nice" can be interpreted from women as flirtatious. I only say this because when we first met...he invited me out to drinks and dinner several times....which I assumed were dates! According to him he just saw me as a friend (Im not sure I completely believe that since we have been together 2 years)...but I had to explain to him that asking a single girl out for a drink...just the two of you...has a romantic connotation. The example I had was he had asked a female coworker out for a drink twice and when we were going through a rough patch (we took a three week break) they had a drunk makeout session at a bar. This obviously hurt like hell but I pointed that out as an example of sending the wrong message. He does ballroom dance - and I also pointed out a few ways I felt like that relationship with his partner was inappropriate such as her constantly sending selfies and saying she needs a hug and get a drink with him. The conversation was calm, progressive and eye opening. I made sure to emphasize that from my perspective, this seems inappropriate. There may be a girl out there who is fine with it....but I am not and that is a boundary I have set. Since our talk I have noticed a significant reduction in texting other women and when its alone time...its just us. To be honest....he had no idea his behavior bothered me and speaking up in a calm and mature matter really helped.

Just be careful that he doesn't think you were snooping through his messages...that's a big trust breaker in my book.

Personally - I think drinks with the ex is fine...drinking with the coworker can be in a group. It doesnt need to be alone.