I was also going to comment on her being in heat the first time and that was why she was so friendly. Now that she is finished she is showing her true colors. I hope this isn't the case though.
The only suggestion I can think of at the moment, is to try and ignore her, but still talk to her while you are going to feed her and going about your business outside.
Gosh if it doesn't rain it pours.
You know we are behind you 100% no matter what you decide as your furbabies welfare comes first.

Good luck and keep us posted on Matilda.