yes this can be a pain to learn. Especially because it's the first advanced move you learn.
What you're experiencing is exactly the reason why many start but few persevere.
Trying the same thing over and over again numbs you and will drain the courage right out of you.
That's why I always talk people into switching things up a bit.
Try it with the seat higher and lower. Add some spacers under your stem and then take them all away.
Start from the back peg and then start from the pedal.
Bend your knee to the extreme so that you get tucked in deep over your handlebar and then stretch it .
Swing your balancing leg all the way back and forth again.
By forcing yourself in all kinds of different positions your body builds up a memory.
These memories may not always be the correct ones to perform a proper hangfive but in time you'll be able to weed out what works and what doesn't.
Try not to anxiously stick to something when you think you've found something, keep trying different things.
Don't be bummed if for example you throw yourself over your handlebar when you put your seat higher, that's the whole point; keep at it for a couple of hours and get comfortable with it.
When you put your seat superlow you'll be amazed of what you've learned.
Regarding hangfive in particular;
Try to get your shoulders over the axle of your front wheel and work that balancing leg.
Also check TJ's "come hither" thread which was conceived especially for the likes of you.
http://www.global-flat.com/smf/index.php?topic=23305.0