It really will vary from school to school and chapter to chapter. I know for my chapter, if you get married or have a kid, you automatically become an alumnae member. I'm not sure how the marriage thing will work.
If it's different at your school and you can go through recruitment when you're married, I would advise you to work very hard to make connections within the chapters. You're going to have to work twice as hard to outshine all the 18-year-old freshman surrounding you. Take the opportunities you have to speak with active sorority members during recruitment to explain your situation and why you've had to wait so long to join a chapter, tell them about your military experience, ect. If you can make a chapter really want you by having a great personality, they will want to give you a bid regardless of age, class standing, ect.
I would also advise you to maybe look into a service/multicultural/religious/academic sorority. Panhellenic sororities are super special and something I think every girl should get to experience in their life, but maybe for where you're at in life right now, a different kind of sorority would be a better fit for you. I'm not sure how old you are, if you're 26+ I would say maybe it's not the best idea. I can't imagine being in my mid/upper twenties and married and wanting to be in a group of girls at least 5-8 years younger than me. It just seems like it would be very awkward, your big would probably be at least 4 years younger than you. I also feel like a lot of girls would have trouble relating to you and see you as a "mom" type. Even though 26+ isn't that old, compared to a bunch of college freshman, it's a pretty large gap.
Look into some other organizations, but if you absolutely want to go through recruitment with all your heart, you can at least give it a chance. Good luck to you! I hope it all works out!
If you're looking for any other advice over recruitment and Greek life, check out my blog. I make lots of posts about my sorority experiences on there.
