Hi, sounds like a bit of a rollercoaster of emotions/feelings you've been going through. But I'd say you've done really well in coming close to identifying your triggers yourself, Already you're showing a lot of insight!!
As for sexuality that can sometimes be fluid, it's not always "set in stone", and if that's the case then that's OK. It doesn't need to be confusing if you just see it as- that's the way it is, you're still you, and you're still fine whatever your sexuality. Maybe just accept the feelings for what they are and if they lead anywhere then great but if not.......then maybe other feelings, another time will.......
And you know you are still fairly young right? So plenty of time to find what/who feels most comfortable/right for you. Much better to "take it easy" and take time to find something/someone who "gels" than trying to logically pinpoint.......or try to "fit" yourself into x, y, or z if it's not right for you.
But do you think that maybe it's worth taking a bit of a step back from "is s/he, isn't s/he?", and take more time getting to know the other person, then maybe you'll get a better or more realistic idea of your true feelings towards them.
Afterall its sometimes the "getting into someone's head"/knowing a whole lot more about them, that's really going to be the make or break bit, and up until then however intense the feelings/however hard it is...........Well you get the idea, maybe slow it down a bit??
And if the second girl broke up, then maybe she just wasn't the right one for you. But when the right person comes along, someone you build a real connection with it's going to last a lot longer than that did. And there will be other people in your life who matter to you.
There's a chance other relationships won't make the mark either along the way, but even so they're still going to be a learning experience and bring you closer to finding someone who is going to be there for the "long haul"/someone who is really right for you.
But you know right now, I'd say that your main focus should really be on you, right?
It's you who needs your attention more than anyone else!! So perhaps focus as much on what will make you feel good, without that needing to be dependent on someone/anyone else? You can do it, you're the most important one in all of this!!
Not sure if I went a little off topic there??? Just let me know if I have, or I'm on the wrong tracks!!
Alison