From what I know, those medications combined in high doses are actually deadly but 1) It just stops breathing which is quite horrible, you might as well just choke yourself and 2) it won't do much since your body is already used to opioids
Anyway, as another immigrant in France I can say from experience that being undocumented is far from hopeless. Sorry if I come off as patronizing and you don't learn anything, but there's so so much help and facilities around and most refugees actually don't take advantage of what they're owed and entitled to. For one I assume you already use AME since you're medicated but it also extends to psychological help and you can get free therapy or antidepressants, especially by asking at a CMP (Centre-Médico Psychologique).
Because you have no family/friends and have been abused in your home country you can absolutely make an appeal (recours) to get your asylum, especially after getting diagnosticated at a psychiatrist.
There are many associations that help undocumented immigrants with papers (even giving free lawyers, who can help with appealing) and charity such as CIMADE, France Terre d'Asile, the Red Cross, Anafé and many others that you can find locally. There's also API which can get your degree recognized in France. For general food and charity you can queue at Restos du Cœur, Emmaüs, Secours Catholique. You can buy super cheap food with the mobile app Too Good To Go or ask the leftovers at markets when they're about to close.
Working while undocumented is still possible, black market work is insanely common and even locals do it because the taxes and charges in France are crazy. A significant amount of restaurant cooks, cleaners etc are undocumented. You can show up very early at markets and ask if they need help. Tutoring, baby-sitting or cleaning through an online platform is possible too. Plus if you keep evidence of your work (like messages or paycheck) it can prove your stay in France and help getting asylum.
You can just show up at a mairie or better a CCAS to ask for help and directions, they know which associations are nearby and available. And lastly even if you get an OQTF to leave the territority it's not much of a deal because those pretty much never get applied, especially if you're a woman and depending on the country you're from the chances drop to zero.
Wishing you best for the future