That's great! In the long run, this experience will be more important than the degree. Sadly, in the corporate IT we never use most of the great stuff we learned at school.

But talking about that theoretical subjects, I had similar issues. But when I really tried to understand, when I translated everything into simple language, tried to imagine and visualize, build mental concepts, I started to be thrilled about the inner beauty of computability theory, advanced data structures or topology. It was just like reading very pure poetry, like learning how the universe is coded. It was still difficult, but it was pure joy. Try to find it too and you'll be glad to go on.