Why did windshield wipers stop working when I tried to use the wiper spray and even after I changed the fuse the same thing happened again?

Did the fuse actually blow? Is the washer pump a part of the wiper moter assembly? Are all the connections clean and tight? Are you handy? If the fuse blew, then there is a problem with the wiper transmission (seized or stuck on something) or the motor is seized or shorted out. If the fuse is blown, there will be a black residue and the internal part is broken. The motor will need to be replaced or the trasnmission (not too hard to fix) unsiezed to make it work.

Other things to check before replacing the wiper motor are making sure there is a good ground to the entire piece. This sounds like the problem to me. How to check? Unbolt the motor, clean and switch the bolts around. Sometimes the space between the motor and gear part gets corroded enough to kill the ground and stop it from working. Sometimes you can use a sheet metal screw between the parts or even take it apart slightly to clean this up and hopefully get it working again. Be careful as the brushes could come out doing this. These kind of failures are very common in 1990's GM trucks, buy the way. If you have a test light or multimeter, these could come in handy in checking for proper ground. Good luck.