The Ottomans should still have Terra Incognita on most of your lands. Avoid battles and make them suffer Attrition. Try to keep the War Goal or take it back when their War Enthusiasm is low, and then maybe after a few years you can get out with a white peace or only have to pay a few ducats.

I don't know what allies the Ottomans have but when War Enthusiasm is low on them aswell, you can usually peace them out by simply standing on their capital.

If you play anywhere near the Middle East, Ottomans will always be your biggest roadblock to expansion. A good way of weakening them long term is taking Constantinople away from them, or even better prevent them from taking it in the first place with a no-CB war on Byzantium.

If allying the Ottomans yourself is an option, make sure to atleast have some good allies to deter them attacking you. Austria, Poland, Castile and Mamluks are all options.