Why do I care what my ex told his family/freinds about me ending our relationship...

...even though it was my choice We were together for four years and there were still things that made no sense at all in our relationship. I've realized what I need, want, deserve, desire and believe what a relationship should be and I didn't have it with him. From my view point when we were together his family and etc seemed way more important then us or me. Now that I called it off and we are still friends, but why do I care if his mother/family really liked me or what his version of our breakup is going to be when he tells his family and friends?
He already told me he told people I dumbted him...which I didn't I said, "I believe I should excuess myself from being your girlfriend because I'm not happy and you have too much to juggle in your life." That's how I ended it. This is crazy I feel sad and relived at the same time ...But note I don't want him back.