I agree with
@Pepper about not canceling your credit card. Lowering the limit and putting it in your lock box are better alternatives. I wasn't necessarily a poor money manager in my early twenties, I just didn't make enough. But despite that, I started a savings plan and stuck with it so it became ingrained in me such that when I didn't save anything, I felt weird. I'll never forget, I started with $6 a paycheck (we got paid every two weeks), then when I got a raise, I doubled that. I kept doubling it. I thought I was
really doing something when I reached $25 a paycheck. LOL

Over those years I learned to manage money very well. I haven't paid interest on
anything since my mid to late twenties. Very importantly, I built up an excellent credit rating. There are definitely perks in doing so.
Marie, I think you've taken the first and second steps to more successful money management because you
1. Recognize that there is a problem that has to be corrected and took the first steps.
2. Lowered you limit and locked away your card to avoid temptation.
Congratulations on taking those much needed steps!