Hi Holly
You know what? I don't think that you will find the answer to your problem in any self help book. You might, but it also might make you look into your problem too deeply. Then you feel you have problems that weren't there before. Every person and relationship is different so no rules apply. All you can really do is listen to advice, but not take everything as gospel.
The addage "you don't know what you've got till it's gone" is true. Think about how you would feel if they really were gone. If this makes you relieved and happy then you know what is best for you. Also, what if they left tomorrow and the shoe was on the other foot? Would it upset you to hear them say they were leaving you?
The best way to find out is to start separating your life by doing things without your partner and to not automatically think of them as well as yourself. Women have a hard time doing this I think, but it comes naturally to men. Working on your friendships with others you might of neglected makes it easier. Once you have stepped outside your boring confines of same ol, same ol, you'll either appreciate the comfortability and boringness of coming home to someone you've known for so long or decide it's time to move on.
Good luck in your your quest for happiness
SAS1
P.S. This is just what helped me realise my partnership of 4 years was not worth giving up on. You might have different circumstances, but over the period of time you have stated, a rut is very easy to get into.
