Hello Smallbutbrave,
I just wanted to offer some support on your post this evening – the threats from your abuser sound really stressful.
Threats around using social media to harass, humiliate, control or intimidate you would all be elements of a wider picture of domestic abuse or coercive control. You’d be within your rights to speak to the police about this if you felt able/safe to do so, as this is a threat that is designed to shame and control someone.
Laws around online behaviour are complicated, as behaviour on the internet moves faster than the speed that new laws are made and changed, but it could be really useful to access some legal advice to get some more information around your rights and options in regards to this. The Revenge Porn Helpline website lists some resources for this: https://revengepornhelpline.org.uk/information-and-advice/police-and-law-advice/accessing-free-legal-advice/
Take care and keep posting,
Lisa