My H has been doing this on and off since our dd was born (maybe before too but i can't prove that for sure).
I found one of his profiles and was quite shocked at what he wrote. Is it normal to behave apparently out of normal character when flirting online? It was quite explicit, and not like anything he had ever said to me.
And do you think that this is cheating?
I personally think it is to some extent, even if you don't meet in real life.
I don't think my H thought it was though, but he promised to stop.
But then he had a 'proper' affair..but that's another story!