My heart is broken and I don't know what to do

So... almost a year ago, before going to high school, I met my classmates. And amongst them was one girl. At first, she seemed really fine to me, it was quite pleasant talking to her, we had mutual interests, and we both loved the same series of books. But at that time, it was just another friendship, and I also was trying to recover from my first real love, which was unrequited, and quite painful. But getting back to what I was supposed to talk about, through one more meeting with her and the rest of my class, and also through some chatting and talking during recess or lessons, I got to know her better. And the more I learned about her, the more I liked her. And I didn't even realise when I fell for her. Through the next months I talked with her, and especially chatting when the second lockdown started in my country. We and some of our classmates had meetings on weekends, but only if the epidemiological situation allowed for it. We were getting closer. In several of those meetings, we were left alone by our friends, and we talked a lot, and they began to ship us. It was happening mainly on Christmas and winter holidays. And I think that it was really one of the best times in my entire life. But since then, it's been going downhill. She had a friend, and after the winter break they got closer together. We chatted less, but if a conversation started, it still was quite a long conversation. During one of those meetings, she revealed to me that she's pansexual, and I when I heard that I already knew that I'll end up in the situation I'm in sooner or later. It probably saved me from tears (at least for a few hours) when I learned that she's got a girlfriend. I've seen that they were really close, and I've seen the chemistry between them. When she told me that she's in a relationship, it broke me completely. I honestly congratulated them and wished them luck and happiness, and I spent the remainder of the time I was hanging out with my friends trying to keep my composure. And late at night, a few hours after I got home, I just burst into tears. I didn't know, and still don't know what to do. I want her to be happy, and I see that she's really happy with her girlfriend, and I don't want to sabotage her relationship in any way, so I can't and won't even tell her that I love her. And it's really painful to type or talk with her, talking only with her, not in a group is particularly hard and scary, because I don't want to break and I don't want her to know. My best friends told me that it'd be best to find someone new, but the problem is that I don't meet a lot of new people, I'm shy and not really easy to get to know, and I don't want to end this love. I think that know I'm in the worst point in my entire life, and I don't know what to do.