where/how are you trying them audrey? ie surface, ollie, wake?
I usually only do surface ones, and the odd ollie bs 180, but for me the prgression started like this:
cut out on your heels and practice doing some bs slides (ie like a butterslide, but so your back is facing the boat). you need to sort of dig your toes in a bit so that you don't catch a back edge. this gets you used to feeling the board release in that direction (and it's fun). once you've got that down, you need to cut out fairly hard on your heels, and then immediately (while there's still a little slack in the rope) flick the board all the way around 180. hold in that wrapped position until you can pass the handle. don't panic or rush. you'll have plenty of time to pass the handle, so wait until you feel it in your hand, then straighten up!
I used to try to do the 180 slowly after I cut out, but a friend told me to speed it up, and it's actually a lot easier if you flick it the full 180 very quickly.
I think you're focusing too much on the handlepass at this point too. do the 180 on the water, hold that wrapped position, then pass the handle. once you can do that, you'll be able to speed that up and bring it all together - ie start passing the handle while you do the spin. at this point though, it sounds like you're trying to do too many things at once. you'll never make a handle pass on the water if you have to rush it!!
p.s. surface 180s are dead easy and a lot of fun at cable, so if you have access to a cable park, try them there too. they're also fun on a flat box at cable if there's a nice easy one. it's fun spinning on rails cos you don't have to worry about digging an edge in.