<human>: Can you summarize the given text in a few sentences?

My GF and I live together, been dating for 3 years and we have had our ups and downs. The last year and a half has been rough so we decided to go to therapy. Things have gotten better in the sense that we don't argue as much but I feel it's too little too late. My GF is a great girl, she's caring and loving and is truly in love with me which is why this is so hard. She hasn't really done anything wrong to warrant me breaking up with her but I feel that she just isn't the one for me. I feel that we are two different people at heart and things will only get worse if we were to get married or have kids. We are opposites with different outlooks on life and different interests. While she is a great person, I just don't feel we are fully compatible. If we were just casually dating, things would be fine but I don't feel we are right for each other to get married too. She also has an extremely low libido and sex has always been few and far between. That doesn't help either. I've thought about this for many months and I just know deep down that I have to break this off. I guess what I'm asking for is advice, encouragement, support. I've never done something like this and I feel very guilty because I know it will crush her. I care about her and it will be hard to see her hurt. Does anyone have any experience with this? Thanks for the help.
<bot>: After a few years I feel my girlfriend and I have grown apart and we need to break up instead of take it to the next level.