I'm a reiki teacher and I agree with yours, it sounds like you're leaving your body during your sleep.. maybe you are not remembering it, you might just recall bizarre dreams, conversations in your dreams or just feel out of place for a little while after you've just woken up, those are common signs you might have been astral traveling
Being an Empath is not easy... I hear you.... do you shield every day before you leave your house? might be worth trying .... it's hard tough I know. I sometimes walk through the town and I can sense how so many people are feeling it's hard not to let it take over me.
The homeless guy sat on the ground, the elderly lady waiting for a bus, the stressed out mother, I feel them all, at once!
It's hard but I usually take a break and try distract myself, pray for them, send healing and visualize myself protected
It works mostly, but I still have days where I want / need to shut away from social interaction purely because the energy can be overwhelming. Like today, I was going to go out and do this/that but I got to the door, stood there for a second and decided nope.. back to my cave to hibernate and relax today. Taking time out is good