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.
Hardest pill i've had to swallow this year so far was learning that no matter how good you can be to someone, no matter how long you've been there for them, no matter how much you love them.. that they CAN & they WILL turn their back on you & there's nothing you can do but detach