I don't know where you got that fake news poster (Photoshop much? LOL) but here is the real one where Margret Thatcher openly defended UK's political and legal sovereignty and stated how EU is so inappropriate given the diversity among all the European countries. She said this in 1995, 20+ years ago. How right she was then and today:
Here is the more famous one where she openly rejected the notion of joining a single-currency European Union while giving up control of Britain's own identity with her famous words "No, No, No!!":
Can't believe we have to spend 20+ years to realize how right she was and tried to go back to do what she wanted to do in the first place. If only Thatcher is alive today to negotiate the Brexit instead of the lame May.