If the windows are sticking or reluctant to go up or down freely, the motors are probably drawing a lot of current. This would be detrimental to the switches and accelerate wear/burning on their contacts, although it's odd that "new" switches would fail so quickly.

At the age of your car, any lubricant in the window mechanisms has probably gone away or turned hard, and the guides and regulators may need alignment.
--
Bob: Son's XC70, my 83 244DL, 89 745 (V8), 98 S90, and XC60. Also '77 MGB and some old motorcycles