Does she like me back and am I ready to commit if she does?

Alright, so I'm very confused and I don't know what to do. There is this girl in high school and we never really talked much up until senior year when we had some classes together. Towards the end of it, we ended up working together a lot more and I got to talk to her, but I had always wanted to be near her and I think I had a girl crush on her or whatever. After we graduated, she went through a difficult time with a rejection from one of our friends (because the other girl was straight) and she turned to me for help and advice. We started to text a lot and not a day goes by now that I don't talk to her. We usually see each other every other day too. She is openly gay and as far as I knew, I was straight but she's making me rethink my sexuality. We've honestly only been hanging out for 2 months, but she is literally the closest person in my life now and I know that I always want her to stay there. And recently I went on a trip for 2 weeks where I wasn't able to see her or talk to her everyday and she had left a week before that and I didn't see her until a week after I came back (so a whole month without seeing her). It was like I was missing something from my life and I always felt depressed and just wanted to be home again because then I could see her. When we could, we Facetimed or messaged each other but it wasnt the same. I've never had feelings for a girl before but I don't doubt that that is what this is. I just dont want it to only be a phase because I don't want to screw up whatever we have (or lose her at all) or come out and then decide that I was wrong. Every time I'm not with her I want to be and it got to the point where I was getting nauseous if I wasn't (right after I'd seen her again when I came back because I think some part of me thought she was leaving again). And recently she's been telling me that I'm cute and it's gotten to be more flirtatious texts than just the usual conversations. When we were hanging out with friends, she pressed up against me on the couch in front of all of them even though there was room on the other side and all I wanted to do was just lean into her. I think I'm definitely in denial and I'm scared of rejection and losing her if she does say no. And we're both about to go to college and I'll be almost 3 hours away from her daily, but she still keeps talking about seeing me and how she's going to drive up to see me whenever she can. We're inseparable and I don't want to be away from her again and I get jealous when she's with or talks about other girls, but I'm not sure if she's doing it to make me jealous (or see if I am jealous). We also always say I love you to each other and it used to be as friends (I know because I started it when I was trying to comfort her), but now we say it a lot less frequently but when we do it feels different. We've also never said it in person before (the closest was on facetime). I guess what I'm trying to ask is am I being paranoid or does anyone think that she might like me as more than a friend too? I've never been in a relationship before, never had sex or even kissed anyone so I'm completely clueless as to how all of this works. Anyones help is greatly appreciated because I don't know how much longer I can deal with internalizing everything i want to say when I'm with her. And is it bad that I don't fantasize about having sex with her too because I'm not sure if that's a sign that I'm making all of this up in my head or not.