This is very common for musicians to say, "I'm sick of playing the same old licks." The problem is a lot of times people stop learning new things because of laziness. It's important no matter how advanced you are to always try to learn something new or apply something in a different way.
I teach about 45 students and I always keep them challenged by learning new material. I have been playing for 31 years and have never been in a rut because every day I ask myself, "What can I learn today?" The day you stop getting better is the day you start getting worse. Some days you may need a break from the guitar, but you can listen to music or read an interview with a player that you admire and it will inspire you. There are countless ways to keep focused on music you just have to be creative about it.
I find that teaching really helps, because if I solve a students problem with something, it makes it easier for me. If you are truly intersted in being a great musician then you will solve any problem any way you can.
I'll end with a quote from John Coltraine, "Work on the hard parts until there aren't any." Guess what? That is a never ending process. I love the fact that I can teach and play guitar for a living and I don't ever take it for granted.
Mike O'Malley's instrumental power trio is called No Walls and their latest CD is entitled "World Abroad". He has been playing guitar for almost 30 years and graduated from Music Tech in Minneapolis in 1988.
O'Malley currently has 45 guitar students that range in all ability levels and styles.