How do I support my gf ( and keep myself stable ) when we both are in our luteal phase?

hi, english is not my first language so this might sound off.

both me and my gf are anxious ppl and we get stressed and overwhelmed kind of easily. to make things so much worse I have OCD and when the luteal phase comes I get so obsessive and needy for reassurance ( I try to hold myself back but sometimes I can’t and it’s tiring for the both of us) and I get extremely hyper vigilant, like feeling really sensitive at how my gf sounds and acts ( which ofc doesn’t help when I want to make my gf relax so that we can both navigate these shitty days). when things get really really bad I’m just so depressed and I feel like she’s going to leave me at the most minute thing ( which is kind of illogical tbh because I know she loves me but still). I try not to externalise it and I think I can do a decent job considering the situation, but I really want to be a better support for her and idk I would love tips for the both of us to get thru it.

my gf as well gets really overwhelmed and prone to crying.

I felt so incredibly stressed out these past few days and I really need advice. I know this is kind of a mental health issue as well and I should bring it to my therapist but she is currently on a summer break!

thank u