My girlfriend (5 months together) said the following on my ex co workings facebook picture of bottles of alcohol. My ex co worker posted the pictures of alcohol on a saturday night around 10pm. Here is the jist of the conversation:

"Wow... where was the invite?!" -my gf
"lol come over and bring joshy" -my ex co worker (my names josh)
" lol thats alotta alcohol....you know im just a phone call away ;) " -my gf
"hmmm... you know i still dont have your number yet U.U " -my ex co worker

I called her and got really mad and told he that the conversation looked skanky.
Am I wrong for saying that?

You should have 'asked' her rather than jumping to conclusions, in a relationship you need to trust her, and if you don't then you are in the wrong relationship.

Take care and be well.