It's not exactly the same thing, but I've been in a 2.5 year relationship where it just didn't feel right anymore and I could see that it hadn't been the same for a while. I told the other person how I felt but even then the other person wasn't willing to meet me half way and I felt like I was just being taken for granted. I asked myself was I happy and the answer was no. Yes it will be tough leaving and I cried on more than one occasion, but now even after 18 odd months. I don't feel like I'm not "over it" and I have wobbles, and miss that person but it doesn't feel like I'm trying to push a heavy weight up a hill.