add one more to the "you didn't quit the band you joined" column.
OP could do them a favor by telling them exactly why he backed out of the project. At least the LS so she knows what you'd be down for in the future. Well, at least I got the impression that you'd have ridden that pony for a while if it had really been a pony and not a rented jackass... Even so, with the band knowing the real reason you bailed, their future reference to you is "dude was interested in the acoustic thing, but wasn't into a bigger sound".
The 'drunk at rehearsal' bit is a dealbreaker right there in and of itself IMHO. At least he showed you that red flag at the second rehearsal.
tldr: no flakey bass player in this thread