I often sleep late too due to high anxiety. I understand what you must be going through, and like you I am also doing everything on my hand to avoid sleep medications and therapy visits. Some changes I have induced that I feel are helping me out
Morning workout (I have forced myself to exercise in the morning so that my body and mind starts feeling tired faster into the night). The workout should be of moderate-high intensity: preferably running or lifting, both is even better
Clean diet, as much as possible but allow yourself to have your comfort food/snack in moderation
Limit alcohol/smoking. No caffeine post 5pm or atleast 8/10 hrs before you go to sleep
Chamomile tea before bed time, atleast 2 tea bags, some nights it's even 3 bags. Melatonin once or twice a week. VitD-Mag supplements as well (you can amazon MagnextD)
Read before bed time, nothing technical/functional/business/economic stuff. Because that gets your mind thinking on higher gears at that time of the night. Preferably graphic novels, memoirs or travel writing (but feel free to adapt accordingly)
All this is more geared towards helping you sleep earlier at night than directly relieving stress on spot, but it helps. I don't meditate, but I pray and that helps. You can try dynamic mediation too - like seriously picking up and playing a musical instrument, or board games (they are great too)
Hope you get through this. And likewise looking out at this thread to see what others are doing too