What to do when a girl's actions change quickly

Long story, but basically I got involved with this girl who ive known for 10 years. She was dating a friend of mine but her and I had been attracted to each other for awhile and have a pretty deep romantic past.

She breaks up with him and then tell me shes been in love with me for years. We hang out and I start returning the feeling. We get physical and we hang out like we're dating. Dinners, movie nights, stuff like that. We agreed not to move too fast but couldnt help it. We also had to put on an act when all our friends were around because no one knows yet. It was tough to do but necessary.

So then the ex boyfriend shows up at her house one night and tells her he cheated on her for the whole 5 years they were dating. Shes crushed. We talk and she tells me she isnt emotionally stable enough to handle our relationship. I told her Id be there for her however I could.

So we hang out a few times, then last weekend she comes over and we start hooking up. She leaves midway through and cant give me a good reason. She told me the next day it was nothing I did and we were cool the next day. Since then Ive spoken to her through text for maybe 2 minutes for over a week. Before this revelation, she would contact me multiple times per day. Now nothing.

What should I do? It seems like she needs her space and I want to give it to her. I also dont want her to drift away. She obviously needs time to work stuff out but I dont want her to give up on what we have because of someone elses actions.

I also feel kinda clingy sending her messages and trying to see how shes doing. Yet at the same time I want her to know Im there and help her if I can.

Sorry its so long but I just signed up for this forum because this has been weighing on my mind greatly. Thanks for any help in advance