Anyone temporarily escaped being FA, only to have it ripped away?

For me personally this refers to being FA with women, as I do have a good circle of friends. But I've had practically no experience with romantic relationships of any kind.

Recently, I got close to a cute classmate, we were talking a lot and it seemed like she liked me. I asked her out properly, she said yes but seemed a little reluctant all the same. We went out on a few dates, had a great time, made out, had sex once, etc... all well and good, and it really seemed like it might lead to something. Then all of a sudden she told me she wanted to be alone (she got out of a rough relationship fairly recently) and that we should not take things further. So I was probably just some temporary support in her mind rather than anything serious.

To most normal guys this probably wouldn't be a big deal, on to the next. But for me, it literally keeps playing on my mind constantly, because for the first time in years it actually felt like there was something worth getting up for other than the usual daily grind BS. And then as quickly as it happened, it was all over, and we don't speak anymore. Worst part is I'll see her around uni and at social events etc.

Although part of me thinks that the fact that it happened was better than nothing (would have just stayed FA otherwise), the other part of me feels like it's worse because it had me genuinely hoping I could experience a normal relationship with a girl, and it was over before I knew it.

Similar stories? Been feeling pretty numb all week