Thinking about no contact 6 months after split

Hey needing some advice. Towards the end of our relationship my (25f, 26f) partner started pulling away and after talking about it we decided to separate so she could prioritize herself during her first year of sobriety. We decided to stay friends however the way we ended it left things kinda open and as a result I’ve been pretty hopeful we may have a chance to try again someday. Thing is, we have a lot of the same friends and although we said we’d keep the friendship going, we don’t talk outside of mutual events and hangouts where we’ll casually catch up but nothing deep or personal.

Anyways my roommate is her best friend and last night I came home to find out my ex was there with no warning whatsoever. As soon as I got there they moved to hangout in my roommates bedroom before I even had the chance to see my ex and although she said hi from behind the door, that was it. I went to my room right after.

For some reason this broke me and I cried for about two hours. Since our walls are thin I could here her laugh and it was so beautiful and gut wrenching that I couldn’t find the courage to ignore it or listen to anything else because I’ve been missing her so much. It was weird because although we’ve seen each other multiple times these last few months I’ve been able to mentally prepare for all those interactions. This left me feeling completely defenseless and it was like my heart was breaking all over again.

Anyways I think this whole situation made me realize I haven’t actually healed at all over these last 6 months, I’ve just been ignoring and distracting myself from the heart ache and I don’t think I can take it anymore. I’m genuinely considering asking my ex to go no contact moving forward but idk if I can do it. I’m just still so in love with her and I haven’t lost hope of rekindling so I’m afraid of losing that chance if we cut things off for good.

TLDR My ex is best friends with my roommate and I came home last night to find she was at our apartment without warning. This reopened a lot of emotional wounds I wasn’t aware of and now I’m considering no contact.