The deal is never sealed. I was sure it was with my ex, because she seemed so in love with me.
But in the end, the feminist propaganda she believed in (her career, dreams, I don't need a man or a family) won over her love for me.
She even seemed angry at the fact she couldn't hate me for something, she said it was even harder for her since I was so irreproachable. The worst she said was: "You always want to appear cool, literally and figuratively."
So you can be this "perfect" boyfriend, she can be very in love with you, and she'll still leave you. The deal is never sealed.