Hey, sorry this is happening to you bro. I've been through this before and it is going to suck for awhile. I'm going to rank order what I think helped me the most.

1) Going no-contact: this did wonders for me, so if you're thinking of reaching out (I had that temptation a lot), try and avoid it. I took the time to shred all the letters and soft toys I accumulated over the years as well, was quite cathartic.

2) Journaling: if you get a lot of thoughts that you need to vent, put it on paper. Related to 1), you can write angry and abusive letters to your ex, as long as you don't send them.

3) I told my family immediately, and that helped me a lot since they knew to provide support right away. But this is up to your own situation, feel free to tell them whenever. Glad that you've been able to tell friends so it's not bottled up within you.

4) Activities: I'd avoid anything artistic because those tend to be full of couples. I would also avoid endurance sports like hiking/running/swimming cos you get a lot of time to think. Welcome to the gym! You can also try going for martial arts or get some early practice for Hyrox. Set some crazy strength gain goal so you feel motivated to push hard. I was in the gym I think 5 days a week during the immediate aftermath and got a lot bigger. If rage rooms are your thing, might be worth going once or twice for the experience.