Keeping conversation short and possibly not too deep maybe the way to go indeed.

As for what I do when I make such a bad comment, tried various behaviours, from apologising immediately to changing the subject quickly nothing had happened.

Surprisingly, the person whom I apologized later turned out to be the most vicious, however I am not sure if that is in a direct relation with what I did because there were more things happening. She was pushing towards ' friendship' while in time telling very inviting his of her misfortunes with her friends. Very complicated, even if it hasn't been in the workplace.
The unintended remark that I made time out totally unexpectedly, and I can hardly think I could have prevented this in a way other than that then simply staying away, which in itself would have been taken as inappropriate behaviour, though.

That being said, I take full responsibility for what I did because I happen to offend also people who do not behave in weird way like that person did.