Err, because the pain that you talk about is not shared. One example (and there are many) would be that the cuts unfairly impact women - although I am sure you know this, it's just you chose to ignore it.
It's called the Confirmation Bias - the systematic error you are falling for - you should look it up, but in general terms it just means selecting information that suits your argument and ignoring all other information because it throws your opinions up the wall.
THere has been report after report, analysis after analysis that shows that the cuts unfairly impact the most vulnerable in society - that's why people keep saying it is unfair and they are regressive. That's why it is funny when you say "cut public services, share the pain"