<human>: We met in college last year, and he is ridiculously sweet. However, I had to grow up to be able to fit into a relationship with him, because I told him I 'couldn't do long distance' at first over summer breaks. I later learned I was completely wrong about that, but it did make me very aware of how much I needed to grow in order to feel like I was accomplishing a healthy relationship.

We've been incredibly steady since our first break, and in November he proposed to me. I said yes, because I am ridiculously happy and sure I want to spend my life with him. But, lately, he's been talking about getting married within the year, which we do not have money for. 

Don't get me wrong, I love this guy. He's sweet, funny, and he understands that I'm battling to let go of my fractured childhood. He's very supportive of me wanting to work in a dangerous field, and all around, he's an amazing guy. But he's also very immature sometimes, and I feel like he doesn't know how to handle money. 

I really want to give us time to grow up together before we jump into this. I mostly want to finish college and find a job before we get hitched, but I know this will upset him. I just feel like we're not ready to get married anytime soon. He's still really flaky about some things, and I need to finish college before I settle down.

What in the world do I do?

Give me the gist of the text in a nutshell
<bot>: Fiancee wants to get married next year, I want us to graduate college and mature as a couple first. How do I explain this to him without upsetting/hurting his feelings?