Being authentic.
Feeling what you're feeling, when you're feeling it and remembering how that was, even if it is painful. Whatever you feel, even if it's hopeless or feeling aparthetic that's still feeling something.

Key is to move into the emotions you want more of, create memories from whatever you can, reflect back and journal if you can, there are even apps to keep a record on what you've felt, or assistance in recognizing what it is you're feeling so you can identify it and tie it in to a memory, situation or experience.

If you feel it, you can heal it.