You don't get discouraged easily, do you? LOL! I can't imagine what went wrong, I suppose I'm lucky in that I've rarely had a leading episode when working on a PP project. It does happen, though.
The only thing I would do differently is to lubricate the patch with something, anything. Lip balm, bag balm, bearing grease, Vaseline, a soft mix of beeswax and Vaseline, something like that. Just smear a little on the patched bullet with your fingers.
Just to double-check, did you dip the patch in water, lay it on the patch board with one tip hanging off, squeegee the excess water away with your finger, and then stick the tip to the bullet and roll it up tightly? Dry patches don't adhere to the bullet very well and can just peel off the bullet in the throat. Some people have made them sort of work, but I'm not one who was able to.