My biggest achievement

I am just filling out a graduate application form and I got to a question that says "What is your biggest achievement outside of study?" I'm at a loss. I know the biggest achievement of my life so far is graduating university, but apart from that I have no idea off the top of my head. The first thing that pops into my head is my relationship with Stacey. In this day and age, having a commited relationship for over six years is not something to be taken lightly. We got together just after high school, shared the university experience together, done the whole long-distance relationship thin and now we are successfully managing to live together. I'm just not sure whether you class this as an achievement or not. I guess it is. I have been able to achieve happiness and love where so many other people have missed out or haven't quite got there yet. To be able to say, at this point in my life, that I know that I am going to be with the same person until the day I die no matter what happens. It's not just something to say, but something I know in the depths of my heart. I also know that I am a very different person that the one I was before I met Stacey. Back in high school I was drifting, some days my spirits would be really low that I just wouldn't want to do anything. It seems a world away from where I am now. I guess now I just have to work out how to say this in a job application. Any ideas?