This may get preachy.
It concerns me when I read in online bridal community message boards about friendships and family relationships causing drama and stress in weddng planning. Such as when a bridesmaid is asked over a year in advance, and then the friendship fizzles out. Or someone was asked to be a groomsman out of some sort of obligation, thinking they'd say no, but say yes. Are weddings being planned to early? A lot can change in a year, and even more in two years. Do you really want to lock in all your decisions so far out from the wedding day? You don't have to, you know.
There are some legitimate reasons for setting a date that's so far away from your engagement. You want to finish college. You want to buy a house first. One of you is in the military or for some other reason is not able to live nearby. That being said, you don't have to set a date right away, either. You can enjoy being engaged for a while before the stress of wedding planning sets in. (Don't bow to pressure from parents to set a date! Do it when you are ready!)
The most popular venues do book over a year in advance unfortanately, so if you have your heart set on a specific place, you just might have to set the date and then wait. But that doesn't mean you have to do all the planning so far out. You don't even have to tell people about the date yet if you don't want to. Realistically, a great wedding can be planned in less than a year.
Believe me, I know how excited you are to get started on planning as soon as possible. But do you really want it to be all you do for over a year? It's okay to look, and it's fun. Unless extensive travel is involved, though, you just don't have to make final decision that early.
It's unpleasant to think about friendships breaking up over being a bridesmaid or groomsman of course. But it unfortunately happens often. People change a lot, especially during their 20s, and someone who was your best friend and assumed maid of honor may not be there for you, for whatever reasons, 2 years later. I'm not saying don't ask, but have some understanding and compassion. Your wedding isn't the most important thing in everyone else's life.