I'm thinking of using my cousin's glamour shot as the photo for my dating site profile pic.
What would make you think it's okay to use someone else's picture for your benefit?
I don't think she will find out.
The more you pretend to be someone else, the less comfortable you will be just being you. Don't steal someone else's identity when yours is perfectly good enough.
But I could be someone else.
If you are trying to date people you need to show who you really are. If she doesn't show up they might get scared of feel betrayed.