I struggled with theory until I started using a MIDI piano roll, and then all the bits I had half-understood came together quite quickly.
I find it easier to learn with visual input as a rule so YMMV, but being able to see how intervals relate, and just stacking the notes of a scale vertically and then pulling the chords out horizontally made things much easier for me, and before long I was writing as fluidly as I was on guitar, and soon after I was doing much more complex compositions than I ever thought I’d be capable of.
Regardless of how you choose to proceed, just keep at it, read as much as possible even if it’s more advanced than you think you’re able to grok, you’ll pick up little things here and there that’ll work their way into your practice. And have fun!
