Memory can free you sometimes. It's a tricky monster.
Here you are trying rigorously to walk out of a long gone love. Yearning for mighty consolation, anything. Anything at all. That could explain. In a quiet couple words, the rationale within the heart ache. Because you remember all the good stuff that love had gotten you.
Sometimes bad memory outlives good memory. But this time, good memory had erroneously outlived the bad one. As luck would have it. The heart cribs. And shrinks. Puts up ugly questions.
Then, one night, you are falling asleep. Exactly half way between being awake beginning to dream, your mind twitches, it unearths a painfull memory. Something you had subconsciously hidden, erased. And it's like God is peeking at you. Reason finds its rightful place. You feel lucky. Safe. Even, probably happy. Memory is one tricky monster.