Getting her on date 2

There is this one girl (quite hot but is in a geek crowd so has the virgin marry affect) that I went on a date with one mouth ago and a half with, after long story short we had fun.

Next week was cool, I tried to invite her out over easter hoilday but she flaked on me twice (I played it off as I was busy as well). All the while we were texting on and off.

I then started to talk and text with her more in and out of class, we both ended up going to a party were desipte me having excellent social proof and flirting she got of with two guys (who to be fair got in there first) and drunk wayy to much and wasa mess and I wasnt in the mood for joining the 3 guys who were trying to Comfort (get off) with her.

But now we are textin mopre and more when ever we make plans she Flakes, how can up the anti sort of and finally get her on another date, espaclly now prom is coming round and were not in all the same classes?

Any help would be great it just seems with me that somtimes trying to get dates with these flaky girls is just tireing, but this one girl everytime I talk to her I do feel alot ahppier for some reason.