Am I resentful or do I really deserve an apology?

Before I start, I'd like to tell you a little about myself. I'm a person who truly dedicates a lot of time and love to friendships. I think about my friends all the time, what to give them, and how to fix it if I did something wrong. Also, I have some issues with abandonment, or rather, with being left out. Now that you know this, we can continue with what happened. About a year ago, with my group (there are four of us) of friends, during a recreational day at school, two of my friends (let's call them T and L) met two senior boys, let's call them H and P. These two boys became very good friends with my two friends, but that's it. What's the problem with that? You might ask, and the problem was that they started leaving me and my other friend out, and they talked about them all the time, and it started to get annoying. Also, I used to talk to T a lot, we used to talk every day, and it's still the case, but during the time I first met these guys, a few months, that was enough for them to start answering me curtly, sometimes not answering at all, and this only stopped when I complained about the subject and they stopped talking about themselves. Although not everything was resolved, they continued to have get-togethers, plans, or things without inviting others, and although I didn't mind that much, it did bother me. Other events happened that I can't talk about, but that led me to wonder, how can a person you've known for less than a year become more important than a person who has been giving their all for more than 5 years? And don't get me wrong, I don't feel like they're replacing me or taking my place. It's not jealousy, I just feel like they're throwing me away like a toy and that they don't care enough to think about how I must have felt when they stopped talking to me. On the one hand, I know them (T and L), they are the type of people who love meeting people and are very happy to have new friends, so much so that the excitement of having someone new can overshadow the old friends. I am the complete opposite. I am not so much into meeting new people. I feel good with the friends I have and I am happy to say that I have a good quality of friends without paying attention to the number. I can be a little repellent when it comes to wanting to meet new people. The truth is that I don't like it. The first few months I wasn't upset or angry, but I did feel sad. Now that I can reflect with a clear head, I'm really angry, and the question is running through my head: should I say something to them or not? They've stopped talking to them, but I keep asking myself if I should say anything because I really feel angry, and all the feelings of sadness I had now manifest as anger, frustration, and sadness again. Thinking that they don't care breaks my heart, and I really love them. They were there for me through many bad times as well as good. They're understanding, sweet, and truly precious to me. But I don't know what to do because I feel like if I say something bad, it's going to happen to them, or I'm going to have a fit, which I don't believe in. Please give me some advice or at least tell me if I'm the one who's wrong, because this has been on my mind for more than three days.