You reek of desperation.
When women say that they can't get hot for "nice guys," who they really mean is guys who try too hard. If you come on too strong, too fast and inundate her inbox with emoji heavy text messages, you need to dial down the thirst.
Wanting a girlfriend is a perfectly acceptable desire, but it should never dominate your life. Women can sense when you're desperate to wife someone—anyone!—because you emit fear and anxiety, neither of which are a turn-on. It also indicates that you're the type of dude who would revolve his entire universe around someone, which is an independent woman's greatest fear.
Focus on doing you and pursue your hobbies and interests. Build a life that any woman would want to be a part of, instead of trying to build your life around a woman.