I married Aela, hoping to get free archery lessons. Or at least cheaper lessons. I mean I put a roof over her head and feed her. Seemed reasonable. But I don't get the training dialogue anymore.

Is this a bug? Or is it the same with any trainer your marry? I can still use other trainers right?

Your suposed to be able to still train with them, as I've never did the marriage quest's I'm not exactly sure how it work's. But wiki does say that your suposed to be able to still train.http://www.uesp.net/wiki/Skyrim:Marriage

I think marrying a vendor would be more worthwhile.

They start their own business and give its profits to you.