If you ended a relationship and realized they didn't go looking for another person, didn't go out partying, but instead started running, training, taking care of themselves, and distancing themselves from everyone so they could overcome themselves... I'm sorry to tell you that they truly did love you.
And I'm sorry to say you let a very good person slip away, one you won't find again... not even in another lifetime.
maturing is realising that there comes a moment where you decide “this is the last time these people are going to make me feel this way,” and you actually mean it. whether it’s family, a relationship, or a friendship.