Getting both down for a nap is impossible, help

The only way I can get my 8 month old twins to nap is to put them in their cots (with white noise, cool, dark room), and leave them to cry it out. It kills me, but I’ve tried everything.

I can stand for up to half an hour rocking them, holding them to sleep, and nothing works. I get too distracted with the other one crying/ screaming/ not knowing where to put the other one, and I obviously can’t hold them both at once.

I have ppd and the nap situation stresses me out to badly.

When I do have help, the other person simply holds them to sleep. I can’t do this on my own, I just can’t. Not with the other one needing me at the same time. I have safe places to put them but the hysterical crying is too stressful that I can’t focus on putting one to sleep at a time.

Is there an easier way? What do I do when they’re playing on the floor then bam, BOTH need a nap at the same time?