<human>: I have been in a relationship with my S.O. for about four years now.  We've been together since 11th grade in high school and now attend the same university.  We see each other pretty much every day in addition to texting & talking on the phone.

I guess it seems like we have a pretty healthy and happy relationship; we're able to get through most problems by communicating and compromising.  We are best friends and always try to make time for each other.  Since we've been together for so long we're very comfortable with one another and have been told before that we act like we're married already.

Here's my problem:  I love this girl to death but I've been experiencing a yearning for novelty in my life.  While the problem does not necessarily originate entirely from the relationship I feel that it may be a major contributor.  It's hard to meet new people on campus when most of my time is spent with her and I essentially feel like I'm living the same life as I did in high school.

Something that is a little frightening at the moment is that she's really excited and ready to get married and have kids with me.  While she seems to be 100% positive that I am the one she wants to marry, I am not as enthusiastic about it.  She has it all planned out and would like to get married in X amount of years and have children in Y amount of years  There's other behaviors I would like to share but will refrain from doing so in order to remain anonymous, but you get the idea--she's sort of that type of girl.  I'm starting to think she's a little crazy...

Again, I really love her and while I dread the thought of breaking up with her, I also see it as an opportunity to experience new people, women, and other things.  Simply put:  life has been stagnant for years and I think it might be time for a change.  Is breaking up the answer?  I am afraid that if I tell her how I feel it will go horribly wrong.  We have a really strong bond and it would be a shame for it to be ruined as a result.

Can you summarize the given text in a few sentences?
<bot>: I love my girlfriend dearly, but I think it's time for a change.  Life has become too mundane for my age and circumstances.  Is breaking up a sound decision?