"I would like to thank all my old classmates from the Italian School for accepting my friendship invitation. I hope/wish we will be more at out next meeting"
Well, it's not clear from context if it is about a facebook invitation. The only clue is that s/he uses the verb "did a friendship invitation" and not "sent...". I chose to translate it word by word because of the word "meeting" (in case s/he means an invitation to the meeting.)