I have been abandoned by others emotionally, and it hurt like hell. It wounded; it was traumatizing.
Trust was abused and lost, and that affected more than that one relationship with one person—it made subsequent emotional vulnerability a risky prospect. No matter whom we get to know, we'll never be immune from abandonment, because people are human.
In retrospect, however, the most painful abandonment I've experienced is when I've abandoned myself. This has happened multiple times over the years.
Abandoning ourselves is an unconscious behavior, sometimes a response to earlier abandonment. Those of us in recovery have a long history of abandoning ourselves, but the good news is we can find ourselves bit by bit.
We can earn back our trust in ourselves. We can be vulnerable again.