I used to be the same, manualling with the front wheel super high and then tapping the brake, slamming the front down and crying myself to sleep at night.
You say it feels easier to keep the front wheel high which is fair enough, you've got a high bb on that so naturally it'll want to sit up like that, and there's a lot less chance of the front dropping, but you really do need to practice keeping it lower - it'll help you so much! Like hop manuals/ manuals to ups etc just don't work if you keep it front. Think of it like pre-loading for a bunnyhop but then just never hopping.
Or if you are gonna stick to keeping it high, are you sucking your arse back in towards the bike or just down lower? If you're still over the rear axle and just getting lower that'd explain why it just loops you out. Think consciously NOT to brake when you're close to looping out. That did a lot for me when I was learning. Thought about a higher rise stem, too? Or a 24"...