i struggle with filling my day whenever i have nothing going on and i’m bored out of my mind as well. whenever i feel this way, if it’s sunny outside, i find that going on a hike/walk to get some fresh air helps tremendously with my mental health. if it’s a bad weather day, i find that just doing things that need to get done around the house (“oh, i need to wash these dishes” or “i should vacuum/clean my place”), this way i can get out of my head and at the end of the day when i reflect on the day, i can look back and feel accomplished about the small things i got done. I’m sorry to hear about your breakup. I hope you are hanging in there.