The more you dig into this Yahoo sues Facebook story, the weirder it gets.

It was risky enough of Yahoo to embrace the patent troll mantle in order to punish Facebook and please activist shareholders. It was made worse by the knee jerk filing of a suit, without any previous discussions with Facebook about the alleged infringement, which just happened to coincide with Facebook’s IPO. Even that was made worse by the fact that the patents in question describe half of the Web.

But the even weirder thing is Yahoo’s strategy for taking a cheap shot at a company that it is hugely reliant on for traffic and — in some demographics — relevance. I found an extreme case in Indonesia, where a Yahoo executive told me that Yahoo email addresses were surging solely because Indonesians needed email addresses to sign up for Facebook.

As Om Malik points out today, this over-reliance may be what spurred Yahoo into action: Yahoo woke up and realized that Facebook has way too much control over its users.

But as our infographic below shows, that hardly happened over night. As with most things in Sunnyvale, if Yahoo is upset about that, it only has itself to blame. Desperate to stay relevant and keep growing, Yahoo continually integrated its products deeper and deeper with Facebook, and now it finds itself beholden to the social networking giant.

If you’re Om, you see that as a reason to file a lawsuit. If you’re me, you look at that and ask the inverse of that: Does Yahoo really want to poke the company controlling this much of its traffic in the eye?

I’ve been digging around and have heard from several sources that there are two camps inside Facebook right now. Those who say the feisty social network should just cut off the traffic spigot to Yahoo, and those who say being an open platform is about being bigger than such petty squabbles.

Still, if Yahoo’s claims were to get traction, Facebook could arguably make Yahoo hurt a lot more than Yahoo can make Facebook hurt.

It’s reminiscent of the squabbles between Google and eBay — except eBay and Google both needed each other. Facebook doesn’t need Yahoo. At all.

Check out the infographic below for details. (Click to enlarge.)

(Huge thanks for to Lemon.ly for the infographic!)