Generally, when they suggest you date it's to alleviate their guilt. That guilt can be due to the fact that they are already involved with someone or just the guilt from not wanting you anymore. If you're with someone else they think that will make them feel less guilty. that means they're very detached.
Certainly, suggesting that you date can be a test to see your response, but by the time we get "here" our WAW's are not testing us, they're 95 percent gone.