I’m sorry to hear you’re struggling so much, but I can tell you it’s extremely familiar to me. But the feeling wasn’t in Battleborn, it was in SMITE, which leads me to a question that hasn’t been asked before:
Do you have prior MOBA experience?
Based on your answers so far and your struggle, I’m assuming you don’t (please correct me if I assume wrongly), and that is part of the struggle. MOBAs are really complex monsters to try and get a grip on, and it takes a lot of time to get even remotely comfortable with the mechanics. BB is even harder than most ‘true’ MOBAs in that it combines the complexity of character synergy, leveling, builds and need for awareness of that genre with the breakneck pace of shooters. It’s an intensely interesting but hard to grasp combination of genres without prior experience in one of those.
How to fix this is just time, practice and working on one thing at a time. Don’t try to work on your map awareness, positioning, skill usage, cooldown management and objective control all at once. Pick one, work on that and let the rest be for now. Like others suggested before me, Oscar Mike is a really friendly character to learn the intricacies with, as he is extremely flexible and easy to use.
Another, slightly more out of the box idea, is getting some MOBA experience somewhere else. I’d recommend SMITE for this, as it’s pretty forgiving in it’s early levels and has various game modes to practice different things in. The pace is a lot slower and the 3rd person camera makes it a lot more recognizable than isometric games like League or Heroes of the Storm.
While I’m no pro at the game, I’m more than willing to run practice and coaching matches with you to try and narrow down the things you need to work on first. It’d be a shame to give up due to a roadblock like this, that’s definitely manageable with some help. Steam name is GreyAethelwulf.

Thanks for the heads up though! Much appreciated.
Maybe PM me a link to your profile? Or just look for mine, Steam handle’s Tobster and I’ve got a pic of like an orange galaxy-type thing.