**WARNING: NO BS ADVISE FOLLOWS. BE SCARED, BE VERY SCARED**
Pick 3 tunes. Burn a CD for everyone.
Everyone go home and work on it before the next practice.
Go through all 3 tunes, and pick out the one ya'll suck at the least. If you have one that doesn't suck, that's even better.
Now, commit to working on that one tune until it is good. If that means playing the intro over and over again for 2 hours each practice, than admit the level you are at, and work on it until it's good.
Take the next part (chorus, verse, measure, whatever) and work on it until it is good. Connect the two parts together and work on them until they are good.
Rinse, repeat until the whole song sounds good.
If it takes more than 3 rehearsals to get one tune down "like the CD" good, then something not worth fixing is wrong. Either pick an easier tune, or find better people to play with. If the 2nd song doesn't come together faster/easier, ditto.
If you are the one holding things back, admit it to yourself and the others, and go home and woodshed until you can play the tune good.
When you come back to jam with the band, and they haven't found anyone better, you've just help improve things. If they have found someone else, then find some other people to play with, only now you have a tune you can play good enough for other people to stand listening to you.
Don't talk about things being good/great/awesome and plan your world tour when things really suck. Be honest, talk about it, and figure out how to make it better. You might need outside help (manager, producer, teacher, parent etc) to help you with this.
If I made you cry, good. Pain, suffering, and any kind of passion makes for good music in the long run. Hope to hear some from you soon.
Peace Hope Love and Joy
Play what you hear
Listen to what you play
Does it sound good?