I have no idea about how people in the UK should react and I'm not a lawyer, but my understanding of it is that if no one involved in running your site is British, it's not hosted in the UK, and you don't have any kind of business relationships with people in the UK, you absolutely should not worry about it or take any action at all beyond making sure you don't sign any deals or offer any products for sale in that country.

They cannot legally or practically do anything to you beyond perhaps blocking access to your site somehow I suppose, and in the extremely unlikely event that they tried something crazy you'd be an international cause celebre with plenty of legal support available. Doing their dirty work for them by trying to block British IP addresses seems inadvisable.