Perhaps part of the problem is that folks like to look at music theory as if it is some sort of monolithic thing that must be learned in it's entirety to be "proficient". There is a good bit of music theory that will only serve very specific circumstances. Perhaps a better way to approach it is as was suggested above: what do you want to learn, specifically? If you want to learn to read notation, don't get overwhelmed by trying to take on the entirety of the operations of western music, focus on learning notation and your instrument. If you want to learn the modes of whatever scale (major is a good starting point, there are plenty of others), focus on learning scales. Pick a thing you want to learn more about and work on that thing. If you can't deal with self-direction learning, find a person to help you. You mentioned improvising. The more familiar you are with the theory tools that are available, the better you will be at using those tools and figuring out what rules you want to try to break. Creativity in improvising comes out of connecting the music in your brain to the instrument in your hands. Can you hum what you think and play what you hum? Zero inspiration? Try listening to something unfamiliar. Play a scale you don't have under you fingers. I took four years of music theory some decades ago in college. The most important part that has served me most was learning to recognize intervals by ear and being able to reproduce them on command. The rules of voice leading in classical choir compositions of a specific era...not so much.
This is far too many words for this subject. In a nutshell, there is no easy answer. If you want to learn something, get to learning it. There is some amount of work involved.
