Mmm. I'm not sure it's healthy to have either main party painting the other, and its supporters, as extreme (communism and fascism indeed), especially in a society where people increasingly lock themselves into echo chambers to revalidate their opinions.
It has arguably been that way at times but not always AC, we both know that. Thatcher's popularity waned with the length of her rule, and she has subsequently been blamed for every ill to have befallen society (particularly in the northern regions, Scotland, and Wales). Another difference is that both of those leaders could hold their parties together, something neither of today's offerings appears capable of doing; would either really be capable of holding the UK together?
Our elections should be about finding what is popular rather than what or who is hated more, and I'm not even convinced that an election now would actually cut the knot, let alone heal the wounds. :-(