I’d like to argue for the other side, if that’s ok. You’ve had some good advice already, and I don’t disagree with much of it, but I think there are some things you could consider that might both help you in the future and make this situation a little less painful.

So, first, I think she handled this badly. She tells you no, she tells you yes, she picks the other guy after all… it’s a mess. And I’m not absolving her at all. But. This was her first relationship. It was your first relationship. You were both learing how to do relationships and getting to know each other at the same time. Relationships are hard. The first couple times we try we mess a lot of stuff up. She didn’t know what she was doing, what exactly she wanted or how to make either clear to you or this other guy. How could she have known? She’s never been in a situation like this. Maybe thinking about it that way will help you find some forgiveness?

As I said, you were brand new to this too. And it’s possible you didn’t handle things as well as you would have done with more experience. There may be some ways in which you contributed to the mess, not intending to, of course. I wonder what you mean, for example, when you say you “stole” her first kiss. Does that mean you kissed her without her expecting it? Without her being ready for it? And it was her first kiss? If so, you put her into a difficult situation. Here she is, having had her first kiss, and now there’s a level of connection between you that she may not have been ready for yet. Maybe she likes you, maybe you’re the kind of guy she would have liked to kiss at some point, once she got to know you better, but it’s too late for that. It’s already done. She never had a chance to pick you as her first kisser, so how can she now be sure how she feels about you?

This may all sound silly to you. You were close afterwards so clearly she liked it and no problem, right? But you shouldn’t underestimate the pressure you put on her in doing that. Of course she liked you before, but now that you’d kissed, she had to either like you more, enough to keep kissing, or throw you away. She had no chance to naturally grow to like you enough to kiss willingly. There’s a reason you’re not supposed to engage in physical intimacy with someone unless you know they want to do that thing, want to do it with you and are ready to it here and now. If you are not sure of that, do not proceed. It messes things up. You messed with her feelings.

You also say you made her choose between you and this other guy before you started dating. This is not unreasonable. Many people like to be explicitly exclusive right from date number one. On the other hand, many people take a different approach and go on casual dates here and there with more than one person to feel them out and make an informed choice on who suits them best. Either can work in growing relationships, but if one of you is one way, and the other the other, it’s not going to work. Because she’d never been in a relationship before, she didn’t know if she was one way or the other. She may have been told all sorts of things about how she should be. All of this comes together when you ask her to choose before she is ready to, and she chooses wrong. So she has to change her mind later. I don’t think that’s her fault, or your fault. It’s just an incompatibility neither of you had any way of knowing about.

But if you want to draw a lesson from this, I would suggest this: if you push intimacy or commitment on someone who isn’t ready for it, they will either tell you “no” straight away, or they tell you “yes” and you’ve just put a time bomb under your relationship.

One more thing: please don’t fall for the myth that someone who stopped loving you never loved you in the first place. It’s not true. Feelings can change over time, and if you believe that myth, it will turn all your relationships that end, and most of your relationships will, into dirt and lies. And they don’t have to be. You can have something beautiful, and then it goes bad and then it dies. But it was beautiful when it started, and you can hold the memory gladly.

I hope you can move companies soon, because yeah, it sucks to be around an ex all the time. I hope your future relationships will be better and end less painfully. I hope your depression and anxiety will get better, because that is some heavy shit you’re dealing with. Give yourself some credit for dealing with that, and a heartbreak.

All my best wishes.