Funnily, I felt the opposite when I learnt to read music a few years back - that even though I was extremely slow, I could now (theoretically) read and learn to play any music, just slowly! You'll get faster and better with practice, as with everything. I'm still slow. Just not as slow. But crucially I'm fast enough that it's not the bottleneck anymore, getting the notes under my fingers is.

Keep at it!