why do each person in a relationship change as it goes on?

I've been with my partner for 15 years and he has changed and grown. I am sure he feels the same about me. I am glad that we have both grown and changed. I think that is what life is all about, change and growth. I'd hate to be stuck in the same rut for 15 years. I welcome change and think it is good. I think growth is good to as long as you do it together and don't grow apart.

Peopla are never done growing. When you are in a relationship you can grow together. However..some do grow apart. I think when that happens and there is no room for compromise..the relationship just wasn't meant to be. My fiancee and I have been together for three years now. I though we were starting to grow apart, so we talked about it, and got back on track.

People do not change because they are in a relationship, they change because they experianc new things and they get older, they kind of grow up. I do know that I have changed .- for the better with my bf.

Maybe i think the one of the reasons why some changes happens in a relationship because they lack time for each other, communication so in a result sometimes they seem to not respect and trust one another.

You do not mention the length of the relationship. If it has been a short time then maybe it is not so much change as it is just getting to know one another better. In the beginning it seems people are on best behavior which may change as they grow more comfortable with each other. Over time as others have already stated situations,experience and growth would bring about changes. Certainly marriage,children,more responsibilties would make changes (hopefully for the best).