Well I don't know where to start... so there is this one girl I have a massive crush on since almost two years. At first we only saw each other at parties with mutual friends. She used to come over to me, drink a sip from my cup and we talked a bit. Basically we always talked about the same topic over and over again, how her father used to be my coach (long story). Then after we graduated high school we both had a full summer of free time as university was only starting in October. We both and our mutual friends then used to go to the local outdoor swimming pool and spend our whole summer there. We started texting a bit, but not too much (I don't really like texting) and she also invited me to her home a few times along with friends. After university started we used to meet up here and then with our friends, but I didn't really had the courage to finally asked her out or something like that. Fast forward a few months, she went abroad. I texted her a few times how she's doing and if she's enjoying her time. After she came back there was a sort of a fair in our hometown, where we first met after she came back. She brought a friend with her, who asked me (while she was standing not far away and really heard our conversation) whether or not I liked her. I actually said I'm liking her a lot, but as soon as the words left my mouth I panicked and added I couldn't say anything else as she was listening to our conversation. Since then things were going differently. While she was asking me to go to swimming pool the year before, she didn't asked me then, when she was going with our mutual friends. Same thing when it's about going out. She asked one of my best friends whether he wanted to join her and our mutual friends going out, but never asked me. So then I started thinking this wasn't going to lead anywhere and I basically stopped talking to her on parties and so. Funny enough on a house party we both attended she asked my friend if I was angry at her. So then I started again asking her if she wanted join our friends when we were doing stuff, what she actually agreed to. Well since then time has passed again, we both hung out at our friends houses a few times, but never actually talked, what I found quite odd and now it's happening again she asked my friend whether he wanted to go out with her and her friends, but never asked me?
So here is my question. What did I do wrong? If there isn't going to happen anything serious I could be fine with it, but I want to be friends with her then at least, but this seems also quite unlikely to happen.