Hey man. I feel you. Im fit. i play sport. i never been afraid. but these floaters cut me down hard.
As soon as you mention the flashes are mainly in your peripheral vision then in a way its good. I honestly believe your vitreous is detaching but its in a position its constantly pulling right now on the retina hence you got the constant flash from the retina.
Entopic phenomena is different. They are little stars that move around in your vision.

but for you and the way you describe it sounds like you have traction on your retina constantly it should stop sooner or later once the vitreous breaks off.

be strong man. If we all can do it so can you.
Keep yourself busy. Join a gym. make some good changes.
I play rugby. Im fit. If you saw me in real lif you would think ah this guy has no problems. But in my head the floaters cut me up so badly I was crying at times too.

what you can do is Floater only Vitrectomy. Its invasive but the new 25g gauge needle leaves no stitches and is real safe. Just specialists always say we can deal with it. I hope they get it some day.
"Sophie Faulkner? Yes Please!"