Well I think there are a few notable posters on MN who clearly think that all LPs are somehow failing their DC because nothing can compare to a two-parent family. However, as I know they are talking shite I tend not to let it get to me. 
I have this personal theory that the smugger the married person, the crapper their relationship is - they're just in denial so have to run you down to prove it. Like NSASMN says, it is definitely easier to be a single parent than married to a twat, especially if you're pretending to be pollyanna and insisting that everything on the home front is absolutely wonderful.
Most married people I deal with in RL as well as on MN are actually very supportive. I think the LP-hating brigade are mostly consigned to Daily Mail editorial fantasies.