Go no-contact! Spend time with friends, Hobbies, Listen to your fav music, Yoga, Exercise! Eating, Hygeine, Sleep, Meditation, Join groups/a fandom, Get out of the house! Sunlight helps, Talk to someone (even a psych/counselor if need be) Nothing to be ashamed of! There's lots of self help apps too. Mend is a good one specifically for breakups!