Because no contact is withdrawal, not just absence. Your nervous system was trained on intermittent reward — cruelty, then relief — and cutting the supply throws it into protest: obsessive thoughts, urges to check, physical ache. The pain is the conditioning unwinding. It peaks, it passes, and it is not a message to go back.
Treat it like recovery, not a test of love. Count days (streaks work), block what you can, re-read your own documentation on the doubt days, and let people feed you. If a slip happens, it's data, not doom — reset the streak and notice what triggered it.