Sticky LDR situation

So about 3 months ago a girl (18F) randomly DMed me (19M) on instagram. She lives a good 11 hours away. Mind you I havent talked to a girl in relationship or talking stage sense in a few years. Apparently I liked one of her posts scrolling insta. We struck up a convo and had chemistry immediately. it wasnt but 3 days and we were having conversations like we knew eachother for years. We literally talked all day everyday for a month or so straight. Eventually I caught feelings. and so did she. I confessed them to her and said i wanted something exclusive and that id be willing to come and visit her. She hit me with a “lets continue talking and see where it goes, because i really like you, I just want to know more about you.” I agreed to keep talking since i really did like her. so about 3 weeks go by and she hits me with the “Can we talk” text. so i said yes and she explained to me that she wants to wait until she graduates next year to “continue talking.” She mentioned she wants this to become something, but with her parents probably not approving a random guy coming to see her. and her probably not being able to come see me. It made sense. It probably wouldnt have worked trying to have a relationship over the phone for 10 months. So i thought this was it, I thought we weren’t going to be talking at all for the next 10 months. But she kept snapping me a little bit. once or twice a day. compared to literally the few days before it was 200-300 a day. and eventually over the period of 3 weeks it got back to talking a lot and snapping like 100-200 times a day. we started gaming together. and having phone calls. she would randomly call me in the middle of the day to just yap. So I was like ok i guess she wants to keep talking like we used to. So i just followed her pace and kept talking. then about 2 weeks ago she started this Hot and Cold thing. she woukd talk to me a lot one day. then the next day it was crickets. then a little bit more the next day. Then she was talking all day the next. then crickets. this pattern has gone all the up to today. yesterday she was blowing me up with high effort and energy conversations all day. today. ive gotten 3 notifications from her. It was her birthday 2 days ago and i shipped her a gift and she absolutely loved it and praised me for it. told me it means so much to her. in the midst of all this hot and cold she also hit me with a “I miss you” text randomly. shes always active on her phone but not replying to me. shell leave me on read for hours then come back apologizing. Im a really bad overthinker so this is really making me lose it. I dont know what to do. I cant really have an opinion or bring this up to her because we agreed to be just friends until she graduates. What should I do?