When I bought my dress, it fit perfectly. I weighed around 146lbs at the time. The only alteration I thought I would need was a slight hem, depending on the shoes.
I didn’t go in for a fitting until about a month before my wedding. I weighed around 154lbs. I could get the dress on, but we couldn’t get it to zip all the way. The seamstress said at this point she would need to see if she could take it out about an inch for it to fit. I was a bit horrified. She also assured me she could do so last minute, and I could wait. We agreed to wait, and we went ahead and did a hem.
I started to eat so clean immediately. Absolutely no pasta, no bread, little rice, no chocolate or sweets. I didn’t drink any alcohol. My meat intake went down significantly, and I tried to limit it to mostly fish. I ate vegetarian probably 3-4 days a week. I had a whole lot of quiche packed with veggies, and a whole lot of spaghetti squash.
So a week later I went in to see the hem, and what do you know, we could zip the dress up! In just a week I had lost a couple pounds. The dress was still far too snug and uncomfortable, but there was hope.
I cheated a bit over Christmas, but otherwise I kept up my super clean eating. Vegetables, vegetables, vegetables, and lots of it! I actually didn’t suffer at all. I ate plenty, but I cut out the mindless snacking I had been doing, and I ate as much as I wanted as long as it was healthy. And the food was good.
Less than a week before the wedding I went in for one last fitting to see if we needed to take the dress out, and we zipped it up without problems! I had gotten right back down to 146lbs.
So there is definitely hope for you, especially since you have time. Watch your portions, watch your snacking, stop drinking alcohol, and up the veggies. Also, drink a TON of water. It really fills you up. Half the time I was hungry, I realized I simply needed a glass of water.
ETA: Also, I didn’t incorporate any exercise. I wasn’t a slob, but I certainly wasn’t active. It really shows that weight loss has way more to do with diet than exercise. And everyone is right about losing weight the days before the wedding. I hardly ate the day before, and I certainly didn’t eat the day of. I just wasn’t hungry because there was so much more going on, and I forgot to eat!