"Holding on to anything is like holding your breath. You will suffocate. The only way to get anything in the physical universe is by letting go of it. Let go and it will be yours forever." Deepak Chopra
We all have baggage, you don't reach adulthood without some junk in the trunk (you know what I mean.) You can tell by your reactions to different situations, that there is STILL work to be done.
Even though you feel that you have done certain issues to death, there is always more work required. The truth is you are NEVER done. That's the whole point, there is always more to learn.
We are here to learn and grow and it's not over until it's over. Nothing ever goes away until it has taught us what we need to know. So it is very beneficial to dig around within and get those issues to the surface.
Once we are aware of what issues we need to work on, we can attempt to let them go. You don't want them festering inside, manifesting into illness. You really do want to discover what makes you tick, acknowledge the feelings, and allow yourself the privilege of release. It is a process, it takes work, to free all the pent up anger, resentment and hurt. But the only way to get what you want, is to let it go.
It isn't easy.... it takes time. It often feels like it'll never end, but it will if you are diligent in regaining possession of yourself. You don't want to let issues hold you back, you have places to go and people to see. When you finally let go something better will come along.
Everything I've let go of has claw marks on it.