You're only focusing on the alimony part, but anyway, if the court says you owe alimony, then you do. If you later find out your ex isn't trying to find gainful employment, you can always have your lawyer try and get you out of alimony.

Almost nobody should complain about paying child support[0] and 1/2 the house. Those are still responsibilities that need to be taken care of.

[0] I left this open ended because there are (very rare) exceptions.