Just a thought: There's a likelihood that not all of us are great in every endeavour we make. Personally lyrics are quite some problem. That is, I had this situation years ago when I created my first lyrics (heavy metal genre). I wasn't really satisfied with those lyrics and haven't written any more lyrics since then. I'm fortunate to co-operate in recording projects where the lyrics are contributed by other, more talented people in this regard. I'm gladly accepting this fact and can concentrate on where I'm good at (I think so).
Also, some things take years to master or even really get into. I guess we can all experience strong emotions, good or bad - that's a perfect basis making you write lyrics/ songs, but for me it's easier to come up with music than with lyrics. One of my music partners has the exact opposite situation: He's great at lyrics (genre: romantic doom/gothic; will edit maybe 5% of them) but relies on me to come up with everything else: el. & ac. guitars, bass, drum arrangement, and, depending on the song, some classical instruments. It works for us. On another project I'm just the homestudio engineer helping out. The only way I'm contributing to the songwriting on that project is creating all the solos (quite a bit of work - metal context with longer solo spots, harmonies etc).
Personally when listening to (other) music I'm not paying too much attention on the lyrics but I'm glad that the guys I'm working with provide good lyrics.
Just let me tell you what effect good lyrics can have: Most of the gothic songs (the first project described above) were created by starting from the lyrics. My partner provided the lyrics, and often that was all the info I received. I would come up with the rest of the music and he was floored ;-) Sometimes he told me he imagined this or that part to be heavier, more acoustic or whatever, those were the only guidelines I had on some of the songs. That was the first time when I started creating music from scratch, having just the lyrics before my eyes. I learned to appreciate this method, it gives me total freedom. On the other project (=solo guitarist) it's the opposite, I'm contributing a small part to almost complete songs.
You might start to co-operate with different people having different 'musical needs', coming from various genres. You say you're playing the guitar. Remember there's the classical, acoustic, electric and bass guitar. And each of them has a wide range of styles/ways of expression. I'd try to learn a bit of all of them (in fact, I did) so if and when you're coming up with lyrics and you have some skills on e.g. 'the guitar' you might instantly feel this or that part needs to have a classical guitar section or a wild rock solo.
If you're into creating songwriter style music with just vocals & the acoustic guitar I'd recommend listening to some tunes of Andy McKee - he doesn't sing but he's playing jaw-dropping percussive acoustic guitar. I think those percussion elements he uses can really spice up your guitar playing in a songwriter context, to my ears this style translates more emotions. It was Andy's music which made me seriously get into the ac. guitar almost 3 years ago and this largely widened my perspective on playing the guitar.
Don't forget there's other instruments out there.
