I think you've done the right thing to close it. You weighed all the variables and made the best choice. I'm proud of you for seeking closure on that chapter of your life! That shows both maturity and the knowledge that its okay to think about self-care, rather than feel responsible for others. The ones who wish to continue in a group can find their way to another one.
Hugs and high fives, girlie!
As for the mood and body troubles............... its the bad food choices - hands down. Get back to eating healthy for a couple weeks and all those things will go away.