Help me afford glasses

When I was young, my parents noticed I covered one eye often. I was covering my right eye because it was crossing in, and that caused me double vision and headaches. I was given glasses and vision therapy, and by the time I turned 17 I was told my eye muscles had strengthened to the point where if I wore reading glasses when focusing I would never need glasses again... but now my eyes are crossing almost all the time. I can't drive because this messes up my depth perception. I can't read or use my phone. I won't be able to see the board when I start college in the fall.
My diagnosis is intermittent strabismus - esotropia. I need to get corrective lenses. Soon after having my eye problems resurface I learned about cheap glasses online, and I went to check if they had what I need... I contacted as many online retailers as I could find and none carried prismatic lenses that are also progressives (I need the progressives because it helps me focus without crossing, I always wore progressives or bifocals as a child). I was told to expect to pay $400-600 for the glasses.
My Ophthalmologist appointment is August 9th and I need at least $600 by then so I can get glasses made in time for college. Please help me. I am having to touch type to send this and cover one eye to check for mistakes. My other option is to turn my head and look at my computer through the sides of my eyes.  I can't look at people I'm talking to because looking at someone who is close makes my eyes cross. It's getting to the point where my trick to uncross my vision (look all the way left and then slowly right) doesn't even help. I end my days with splitting headaches from eye strain. Please, any little bit helps.