Period issues.

I haven't had my period since November and I am not pregnant either. Is there any special diet or foods or exercise I can do to get my period. I am 26, Married to an amazing husband. I am over weight but I have tried everything to try to loose weight. Me and my hubby both are overweight.  He is diabetic too. Please if anyone can advice me on what to do. We have been married for 2+ years and have been trying for a baby since exactly a year. Plz advice or help me out on what we can do to have a better chance at being pregnant. It's really frustrating now.