My mare was very very green when I got her (Who lets a 23 year old horse still be green? Seriously. Haha) and I also found myself very frustrated with her.
I figured out though that part of my frustration was that I was asking too much (too many things, I needed to focus on ONE thing per session) of her all at once and since she didn't really get what was going on, she was getting frustrated with me. Then we were just engaging in this vicious cycle of frustration at each other.
Once I started focusing on little things, like going on a trail ride down the road (easy since she's also pretty bombproof), or getting an immediate stop when I say "ho", or something similar that was mildly challenging but not impossible for her, I started seeing much better results.
For instance, Lacey used to have a problem with rearing when I asked her to back up, and it turned out that I was just asking for too much backing up at once. Instead of requiring 5 steps of backing up right off, I needed to ask for one until she was ok with that-then two, etc. We had been struggling with backing up for literally months but when I started small, we were able to progress to backing up for as long as I wanted within about a month. I just needed to start out at her level so she understood what was going on.
The successes really made me feel much better about my riding ability and my horse, and it really helped me see how she was thinking which led to even more success since I was able to figure out how to work with her best.
Since your boy is bombproof, is there anyway you can get him out and go for a few long trail rides? I've found that there is nothing like a really long ride for a horse that 's relatively green. Trotting and cantering for long stretches taught my girl how to make her trot/canter slower and faster better than anything I could have taught her in the arena, for instance.
Also, just running is really really fun, and relaxing for me. Nothing like coming back from a good ride where you just went out and enjoyed what your horse does know (and in doing so, taught him/her some things).
You can do it! I know you can. :)
Fabio - 13 year old Arabian/Lipizzaner gelding
Hazel - 14 year old Angora goat
Atticus - 4 year old LaMancha/Alpine cross goat
Rest peacefully, Lacey.