I don't currently have a Screenshot, but in my France game (starting at the Revolutionary France start), I invaded Switzerland, which led to me, Spain and the USA being at War with Great Britain, the Netherlands, Bavaria, Tuscany, Prussia, Hanover and Hesse. 2 years later, I was on the winning side (me and America were occupying all of Britain's American territories, and I had annexed Switzerland). Suddenly, America made peace with Britain, taking only one useless Canadian territory, while most of India, as well as Persia, declared War on me (most nations without a CB, even). Very soon after Annexing Tuscany, loads of nations declared war on me due to my high infamy (I thought my infamy limit was 30.00, as it was there last time I checked - My actual infamy limit was 25.00), while Spain broke our alliance and wouldn't really, nor would America join me in my wars.
Currently, I am war with pretty much the whole of the HRE (including Austria, which has an army at least double the size of mine) except maybe about 3 countries, as well as Morocco, Algeria, Naples, Sardinia-Piedmont, Manchu and Korea. The fact that countries keep funding native uprisings and rebellions in my colonies doesn't help.