Home is where the heart is. Obviously EOS didn't have a physical heart (and obviously the physical heart was in the ribcage not in the home, but that's besides the point). Metaphorically she had a heart. She hadn't had a home before, not one she could remember.
Home, she supposed, was Thunderbird Five.
After nearly two years with International Rescue she decided home wasn't Five. Home was John, because when John was on Earth she missed him, and Five felt cold and empty, and she counted the seconds until he was due back.
She pretended she wasn't terrified he wouldn't come back to her, she couldn't bear it if she was abandoned again. She hadn't meant for him to mean so much.
He meant everything.
