Difficult you bet, but not impossible.
I work with an xabf and am tempted 8 hours every day to contact him.
So far it has been 2 years of No contact and my life is messy as it is without him.
I just do not need his drama, his selfishness, his rage, his issues. He is not a solution or even an enhancement to my life anymore.
What I want to say is: "things can be very difficult and maybe you are tested every day and every hour, that does not mean your resolve is not stronger than that"
Mourning someone that is still alive and around and close in some level is very very difficult. I believe I am still in that process. Therapy is helping me let go of him and my past in general. As barb says: "same planet, different worlds"
Your sanity is worth way more than anything she can offer at this time.
All the best.