Is my father flirting with me?

My father is not a "good" man. He was physical/ emotionally abusive to me, possibly sexually abusive to my older sister (she said so once but refused to ever talk about it again) and he was in and out of our lives our entire childhood. We usually only see him once a year at christmas. We grew up in a very rural (think white trash) area. He is now on wife number 3 and has a toddler with her. He just got facebook (and already has more friends than me) he found me on facebook and left an odd comment on my profile picture. He said "U R so beautiful princess, love U forever." then his wife said, as if she knew he was flirting, on my picture "She's beautiful on the inside." My whole childhood he never called be beautiful or princess or anything like that. It made me feel odd. I'm a young lady now and look just like my mother his first wife, who is quite girl next door pretty. Is my dad being inappropriate?