Oh, morgan...I can only offer a hug {{{{hugs}}}}...I know how much it hurts when it washes over you like that, and/or takes you off guard.
I know that I have struggled with this very thing, but I can tell you the advice that IC gave me:
Make a list of things to do, people to call. Set the timer and allow 10-15 minutes to feel what you feel, cry if you must, then do at least three things from your list. Try to throw yourself into the activities as much as you can. It will be hard and feel awkward for a long time, but it will hopefully break the self-destructive thoughts.
