People like this are best left off your friend page, so I wouldn't shed any tears over it.
In general I delete comments when I know they are going to incite drama. Used to keep them around but after the drama-spam galore of B and A, I decided best to just keep my journal that much less soap-operish. Had another one awhile back, deleted it because the individual managed to miss every point of an article, instead putting his own view. Later on, he posted on S's page (after S wrote about dealing with a ton of crap) about 'it gets worse buddy, get ready for your relationships to fail next to' which I felt was rude at best, not to mention stupid - if you really feel this way why the hell tell a friend who's already dealing with crap? Anyways, neither me nor L took joy to it, he responded back snarkly, someone else joined in and 9 posts later mini-flame going on. So, I try and avoid that on my lj
