When could you just.... not do it anymore?

I'm 27F, he is 30M. 1 year, 3 months since dd. Tale as old as time with his coworker. Cheating? Fine. Been there, done that. He ghosted me after a 6 year relationship and buying a house together that really fucked me up. Got back together because of a chemical pregnancy. Then it was just easier to work through it.

Reconciling has been fine, more work on my side. The biggest change in the last 3 months is that I quit smoking weed. I knew that I was numbing myself through the last year to cope with the thoughts and nights alone - he works out of town 5 days a week.

He has recently added a 20 year old girl onto his crew and they are all living together in a condo. A group of 3 guys, 1 chick. I feel sick most days but, i know that i can't sit and think and worry 24/7.

I woke up today and just... don't want to feel this way anymore. If not this female coworker, then who? If not this job, then what one would i feel safe with him having? Will he wake up tomorrow and decide to nuke our entire life together again?

I knew the moment i would stop weed that everything would be felt x10000. Is it the lack of weed talking? Am I just in my luteal phase? Have I thrown away my year of "healing" because I was just numbing myself?

For any of you that reconciled and then ended the relationship on your terms: how much time did you sink into reconciling before it could just not go on? I would also like to maybe hear from some people who were coping w/ substances and then ended up quitting.

Thanks.