Glad you're feeling a little better today.
I think you know to try to distract yourself when the thoughts come rather than letting them invade and ruin your days. You will be aware it's unlikely he is letting them ruin his, and the only person who it hurts is you.😔
As for social media, as you know i think there is an argument for ripping the plaster off fast, and becoming immune to what they do, by seeing it. Taking the no social media route and not knowing will work, but not if you then sit spending time imagining what they are doing and getting all upset about what you're imagining. To be honest, that's probably a lot worse.
I think if you're going to continue to not use social media, then try really hard to make a pact with yourself not to sit imagining it instead. Force your thoughts elsewhere. You know you can do it.
Or reactivate, find out, and get used to it, as much as it may or may not hurt immediately at least you will know and not be imagining it and you will just get used to it and bored of it.
Your mutual friends will have been seeing it for the last three months or so, so will be used to it by now, they probably don't link it back to you anymore.
Going back on social media would be a sign you're happy again. Plus let's be honest, you can post pics of your own happy shit on there if you wished to. Social media only shows what people wish to show, not the whole story.
Either stay disengaged and force yourself not to imagine it, or engage, know and get used to it,,,💐