BB, is there anyway you can adjust your availability and tell them you can't work more than, say, 10-20 hours a week during specific hours so you can have a somewhat regular schedule? At my last prolonged job they had me working 60 hour weeks but then eventually I told them I can only work the evening shift 5 days a week so that cut me down to 25 hours a week always from 5pm-10pm and it was soooo much better for my mental health not to mention the evening hours were so much less stressful than the day time hours at that specific job. Work boundaries are important, especially for us sensitive to stress.