You can secure yourself with fear, until the day
when you have the wisdom to understand that to love means having to
open yourself to 'infection'. And there is always that risk, since
you open your soul to a complete stranger with the advent of
Love.
You can be overly self protective, but at the end of your day, your
growth is minimal.
The only person who has never encounter failure in relationships
are those who never try.
You may have craved to love and be loved deep inside, but your
automatic thoughts for the fear of hurt may be stronger than your
desire to be in a fulfilling relationship.
Nurse your wounds from within - four years is a long time to be
dwelling over past issues. Don't waste another four years being
overly affected by the past because it may come a day when there is
someone suitable, but because you are unstable, you bring on your
instability onto her/relationship and cause emotional fissure.

Cheers