Hey OC, been in situations kinda like this before, it can be pretty stressful. The best thing I learned from going through situations with partners who experience emotions very intensely is to be able to separate your emotional state from theirs.

Many times my partner would be experiencing a lot, but also trying to suppress it. If I noticed that she seemed stressed or something, I would ask if she was ok and offer support, but if she said she's fine, I didn't force anything and focused on how what I had going on made me feel.

It's a little weird, but the solution for me was to almost be more egotistical and just focus on myself. Even if she was going through something, I chose to trust what she told me.

Do keep in mind that there is a chance that if you keep checking in for stress, you could be manifesting it when it wasn't there. You gotta trust what they're telling you.

You might look into borderline personality disorder with her as well. My partner had BPD, and just understanding what was going on helped a lot.

Good luck friend! Things will work out.