Hi George, i feel you on this one.
my advice would be to have a break from it. Arrange a dep and tell the lads you are having a few months off, and hope to be back.
i found the monotony of playing the same songs - more or less - for 5 years a downer and really hit my enthusiasm for something i have always loved. When i left i found i was playing stuff i had not looked at for ages, and being invited into other bands etc. Also i started learning keys which i never had the time for before.
its been about six months now and just thinking of getting back in the saddle again, so to speak.
leave the door ajar, rather than slamming it closed, and give yourself time to breathe and think.
hope this helps George, and good luck,
Mike