I've been playing guitar for 13 years, and I still am not very good.

A breakthrough for me though, was when I stopped obsessing over getting every note right, and instead focused on strumming the right chords. Then, I found playing much more enjoyable, and it was easier to play whole songs and sing.

Once I got that down, I was able to move on to more complex things. Like many things, it helps to embrace your suckage with musical instruments.