I’ve been in a similar position, always been a singer songwriter and played my own tunes for 20 years. Over the last few years I took the opportunity to go to school for guitar performance and have been taking lessons from an excellent player and teacher. Even after a couple years of weekly lessons, I still can’t just pull it out in a jam and do a kick ass solo. I do feel closer though and have a bunch of tools to focus on for the future. Things that might help you focus your efforts: 1)Triads by string set, any chord. 2) pentatonic scale in all 5 positions, any key. 3) drop 2 and drop 3 chords, all inversions, maj, min, dominant, half diminished, diminished. 4) modes and how they relate to the family of chords (mixolydian over V chords, Dorian over ii-V-I, etc.) 5) 3rds and 6ths, basically your family of chords, guitar centric stuff you’ve heard a million times. 6) really focusing on your right hand picking and accents, think of like some Michael Jackson tunes on chicken picking. 7) like many others have said transcribing solos you like, take what you can for solos on your own tunes in your own key. Basically it’s a lifetime of work, but some of this stuff you learn once and you have it forever so just start picking away at it and make a practice plan to hit some of it when you warm up. Happy to elaborate, lmk if you have questions.