We had this happen a few times with Google. Reading this brings back the feelings I felt at that time; the feeling of being powerless to something 'unfair'. I guess everyone had that one time or another. The reasons why things like this happen are debatable; maybe Google/FB has their reasons to effectively ban companies giving them hundreds of thousands to millions of $ / year (as these guys were and as we were). They are a commercial company and they can decide that and they do decide that. What the infuriating thing is, is the canned response communication. I cannot see that happen in many other business contexts in the world; if you are a $100k or more per year client, it seems totally insane that you get treated like that (actually; I'm not sure it's legal in some countries). The fact you cannot even call someone to just tell you what's up if completely weird. And the reason we will never depend on any 1 company for anything anymore.

This is smart advice always ofcourse, but, for instance, with adwords or adsense, for a long time you really didn't have a choice ; the rest is/was just garbage compared. Adwords has gone downhill a lot and this is good news for Facebook, Bing and others. Adsense still pays most for a lot of niches so a business just depending on ad sales will usually find it hard to diversify.

Now we used adwords for dating as well when Google just removed our ads for various reasons they never told us about (they didn't ban the account, they just told the ads would no longer run) and we did something which i'm not sure will still work but maybe it's worth investigating; we went 'local'; we found sites to advertise on and offline means in all parts of the country and got ads there (cheap) which turned out very effective. Especially on smaller local buy & sell sites / papers etc this returned far more than Google. A lot has changed so i'm not sure if it helps you any, but that's what we did and our profits jumped up with the added bonus that suddenly we had no dependency on Google anymore.