Aitk for getting mad at my boyfriend?

So my boyfriend (m23) and I (f21) have been dating for around 5 months and know each other for 6 months now. We love each other very much and have told our families about our relationship.

We both are from different states but for studies/work are in the same city. For diwali, he went back home for around 2-3 weeks. Due to my college and his changing work schedule, we could not talk much. And this I think put a strain in our relationship.

I don't know if this was a factor or not, but he texted me that he's going to meet a friend. Since he was visiting home I didn't think much of it since we all reconnect with our friends when we travel back home.

During this time we didn't talk much since my college had me swamped with work. But, two days after his meeting with his friend (which I had completely forgotten about since it seemed so mundane) he texts me "please call me, I have to tell you something serious". Me freaking out, call him immediately, thinking what could be up. Here he tells me, that the "friend" he met up with was actually a girl who had previously (maybe still) liked him. And they had been on a date before. I knew of this girl since he has mentioned her a long time ago. What I didn't know, was that they were still "friends". Regardless, I asked ok, what happened?

He proceeds to tell me that she snapped a few pics of them together and posted them on social media. Another shock to me since we don't post each other on our socials (he thinks nazar lag jaegi) and he readily let this girl post him. Again, I've had friends post with me too but this was different since my boyfriend isn't an active poster.

Still, I listened on. He tells me that some of her friends replied to her story asking her if they were together or if she was on a date with my boyfriend. Mind you, this happened two days before my boyfriend called me. And she kept him in the loop about all this.

At this point, I cut him off and i ask him if he has told his "friend" that he's in a relationship. He says no, he did not say anything to her about dating anyone. I asked him then what did you guys talk about? Apparently they just caught up and chatted about how their schedules perfectly aligned to hang out that day. I asked him why didn't he tell her he's dating? "Babe woh nazar laga deti". His exact response. But apparently she was very keen on sharing about how she has just gotten out of a relationship.

So, he went to hang out with this "friend" and she posted them on her socials (she's got quite a following) and her replies indicate that she might've gone on a date, and this happened two days ago and he was simply replying to whatever she was telling him about the situation.

So I asked him why are you telling me this? He says that she's asking to hang out with him again "to make people jealous". At this point I'm livid. Because what the hell? What am I even supposed to make of this situation. So I ask him what is he going to do? And he tells me he doesn't know that's why he called me.

I was beyond mad at this point because not only did this man go out with his ex but didn't even bother telling her he's in a serious relationship and is considering going out with her again?

Still, I reeled in all my anger and asked him what he would do if the roles were reversed? What if one of my exes was visiting the city and asked to meet up, posted me on socials and then told me his friends think we're dating? My boyfriend said he would be okay with it, since I'm seriously committed to him. This completely blew me over because how could he? It really seemed like he was trying to cover up his fuck up.

After this, we went back and forth and I just could not figure out why he would tell me this at all, and why he would do such a thing in the first place. So I told him I needed time and i cut the call.

But his response to being okay with the roles being reversed really makes me think, aitk for being mad about this?

I know i have to call him back and sort this out and i will, I'll update if ppl wanna know. But should I just let this go? Is it really serious?