If this is real, just be close with her and don't let the ex thing get in between it. Make it out of genuine feeling for another person that you want to be there for her.
Because if your past threads I'm going to say your life either sucks or why would you ever joke about these things. Thats not even something to troll about. After someone I know having their dad shoot their mom and shoot himself I have no patience for this shit. Its not funny.