She can bring a date or not bring a date, whatever the hell she wants to do. Stop talking about people like they're clinical examples or something. You believe what you want to believe and let them believe what they want to believe and do what they want to do
It's not your job to "diagnose" her as having a fear of being single.
Basically stop talking about like she's not standing right in front of you, which she basically is.
I feel sorrier for people who try to make someone think there's someone wrong with them for feeling a certain way than for someone who has a "fear" of being alone.