AITAH for telling my( 27m) gf (24f) that her male coworker texting her every-time he’s drunk crosses a line

I want to start this off with saying that I trust my gf 100%. I don’t think she will do anything bad or inappropriate with her coworker but her coworker on the other hand I don’t trust.

My gf, we can call her Sarah, started working at her new job about 3 months ago. She gets to travel a lot for her work and would sometimes have to spend the day at their company’s office in another city that’s 2 hrs away from our city. She probably goes there once a week. Sarah is a very friendly and caring person and can become friends with about anybody, which is one thing I love about her. So it wasn’t a surprise to me that she made friends with her coworkers at the other office. She told me about one coworker, let’s call him Sam, that she’s gotten close to. She’s mentioned Sam a couple of times, but nothing bad. Mostly just work drama so I knew little about him other than he doesn’t like his current position in their company.

Last week, on our way home from a family party, Sarah told me that she might have to call Sam because he was drunk and spiraling and needed a friend to call. Understand, it was already 1am when we were driving home. She then told me that he often gets drunk and is probably an alcoholic, and that he cones to her whenever he starts spiraling. I also learned that he’s in his mid 30s. Which was a surprise to me because I always imagined he was closer in age to her since they were able to become close pretty quickly. Again, I don’t think that Sarah is going to do anything wrong and does only see him as a friend, but I can’t completely trust Sam especially since I’ve never met him.

Sarah and I makes it a point that we are always honest with each other even if it might result in some disagreements, so I told her that I did find it weird that Sam would come to her when he gets drunk or whenever he’s spiraling because of the age difference, the fact that they’ve only know each other 3 months at best, and that he is a straight guy. I also told her that even though I do think it’s weird, that I was fine that they were friends and that she can call him if she wanted to help him out. That was the honest truth, at that time I really didn’t mind if she does talk to him even though I thought it was weird. Ofc she was a little upset at me, because she thought I was making their friendship into something it wasn’t. That I was reading too much into his intentions. Which I disagreed with because I really wasn’t thinking too much about his intentions (it was in the back of my mind, but not the main thing why I thought that their friendship was weird) , I just found it weird. We ended the night to kinda agree to disagree.

Fast forward to two nights ago (a Monday), Sarah was showing me a video on her phone when a text from Sam popped up. All I saw was “I’m drunk.” I didn’t think too much of it at that time but I brought it up when we were winding down to go to sleep. I told her that after thinking about it, I didn’t think that it was appropriate that Sam would message her when he’s drunk and that it was inappropriate for her coworker to be doing so. I also told her that it was probably a boundary for me that I wouldn’t like to be crossed, atleast not until I’ve met him and judge for myself that he’s a decent guy. She got very defensive and mad that it was something that I would bring up. Even though I told her that it made me feel uncomfortable because of a lot of reason(the age difference, short friendship, him being a straight guy, and that they’re coworkers) her defense was that I’m only uncomfortable with it because he was a straight guy and that she’s allowed to have straight friends. No matter her explanation or defense, I held firm that it made me uncomfortable and that it was a boundary that I wish for her to respect. But that conversation didn’t really go anywhere and she just kinda ended the conversation when she stopped talking back to me. I feel like she thinks that I don’t want her to have any straight male friends, which NO, I don’t have any problem with that. Most of my best friend are straight women. So it would be hypocritical for me to be upset that she has straight male friends (she has bi guy friends that she says I had no problem with as if that proves that it’s only because Sam is straight that I’m uncomfortable with him being her friend and drunk texting her)

The next day, the atmosphere between us was kinda tense and I tried to talk to her again about it but she signaled that she doesn’t really want to. I could tell that she’s probably upset about it. She also wasn’t addressed yet whether or not she’s going to set boundaries with Sam, at least letting him know not to text her when he’s drunk during the weekdays.

It’s driving me crazy because I thought my request was reasonable. We’ve been dating for 3 years now and I’ve never had to set boundaries before (neither has she), but I thought that this situation needed it or atleast she needed to know that I’m uncomfortable with it. I didn’t expect her to be that upset about it and undermine my feelings.

Tldr AITAH for being uncomfortable and setting boundaries about my (27m) gf’s (24f) coworker (mid30s m) messaging her every time he gets drunk or is spiraling given that they haven’t known each other for that long.