Should I stay with my girlfriend, or is it time to move on?

My girlfriend and I both (both 21) have been in a healthy and happy relationship for two years, but now I fear we’ve reached different paths within our lives.
I’ve just finished my Bachelor’s Degree and am about to start a Master’s Degree in a different city. After this, I have career plans and also want to travel and live life a bit. I feel ambitious and driven about the future and want to live life to the fullest while also building a career that would allow me to provide for my future family.
My girlfriend, on the other hand, is in neither employment or education and hasn’t been for around 18 months and most of our relationship. She’s had to take time off to focus on her mental health, and I’ve done my best to support her through this. She doesn’t really have any solid plans for the future. When I told her my plans, she was concerned.
She says she envisions are simpler life and feels ready to settle. She’s pessimistic about our relationship if I were to pursue my own goals. I’ve tried to explain to her that the property market is hard, and I need to earn decent money if I’m going to provide for both of us, but she says she wants a simpler life than that.
It’s just that at 21 I feel far too young to settle, and I’ve already applied for Master’s degrees and have family and academic support. There’s so much I want to do before settling, and I’m not too sure where she expects to live or where the money is going to come from.
What should I do? I love her and care about her, but are we just on different paths?