okay, so maybe you can think of ways how to achieve that?
I am sure you already did. sometimes something we need is right in front of us and we just don't see it. I'm sure there is a way even if it's not so obvious. (sorry if that sounds naive. believe me I am not.)

maybe somebody else can see it more clearly. do you know someone who you could ask for advice?
maybe you know somebody who was in a similar situation before and managed it.

I think talking to your girlfriend is very important though. she has to be on your side. maybe you could describe to her how great your life would be if you achieved to have more money and time. if you say it in a way she wants it too she will help you and it's so good to have another person who is working with you to achieve what you both want.
and I think she wants that if she doesn't get the impression she was a part of the problem but rather someone who is on your side.
sometimes it's tricky to talk to people we're close to in a way they don't get it wrong.