Because of my girlfriend I turned down my dream job and I feel like I will regret it forever.
What about your dream job do you think you will most miss out on?
I would have been able to learn a lot of things from that job.
Relationships are important but so are your dreams. If you are scared and don't go after your dreams you will regret it later in life.
I love her so much
It's good that you love your girlfriend, but you shouldn't have to give up your dreams for a relationship. These two things should be able to coexist and I'd recommend you take time to evaluate why you feel the need to give up the things you want for your girlfriend.