I was having a conversation with a friend the other day and she said her friend asked her what she considered cheating?  She said her husband reconnected with an old high school sweetheart on Facebook.

The woman is married and she has a family and they live in another state.  However, her husband and this woman chat on Facebook and that the chatting is somewhat flirtatious.  He's telling her they are just reminiscing about the old days, not flirting.  Her friend thinks that her husband is cheating and being disrespectful.

What are your thoughts?  Is this cheating?  Does this lead to cheating?