As mentioned, 3/4" garden hose end threads are essentially unique to this application. A coarse thread 3/4" nut isn't the same and will just make it worse.
Try what Clint suggested - a slim taper file and see if you can clean up the male thread enough to get the hose to start. It just needs to run up 2-3 threads (in the proper place), and it'll cut itself the rest of the way.
If that didn't work, I'd get something with a nice sturdy brass/pot metal female hose connection (NOT plastic), and VERY CAREFULLY, use that as a die. Something similar to one of the ones I show below, but with the washer removed during this step.
Make sure you're holding it nice and SQUARE to the male, and gently start/stop/back-up/restart in order to re-cut the thread.
Then when you're all done, install a NEW washer. If it continues to weep a bit, wrap the male thread with a few rounds of Teflon tape and tighten snugly with a wrench.
Also, use a hose with a METAL female end. The plastic ones deform too easily, and when tightened often crack (and leak).
You should be able to salvage even the most buggered up connection.
Edited add - I like the Superior die Clint suggested. While it'd rarely be used, the really nice part about it is it's tapered (like a die) and should make centering on the buggered male a bunch easier. But again, with a little finesse and going slow, one of the other options should be fine...