Time to grow some balls.
You're going to have lots of fun losing 25% of your customers (more or less depending on regional IE usage), many of them companies with oodles of cash. Heck, here IE usage is 14% while Firefox is 31% and Chrome 47%, according to StatCounter. Not as bad as the US, but still a huge piece of the pie.
Sure, it makes technical sense - IE sucks (well IE 9 and 10 are much better, but still).
It makes NEGATIVE NINE THOUSAND business sense - you've got to be crazy to refuse to support IE 8+.
That's where the "balls" part comes in: you have to tell your users, that you just don't support their platform. Happens all the time, but for some reason browsers are treated specially and we all live in fear of losing the IE market share.
also it sucks.