help,
i am getting married in September 2017, we have had the venue booked for months. I chose this venue because I don't know anyone else who has had a wedding here, is beautiful, and something that can be special to us.
my fiances brother just got engaged, and now my future sister-in-law want to book the same venue for about 6 months after ours

the thing that's really bothering me is that they haven't even asked how we feel about it. My fiance's brother called to let him know they might do it, and there was no stopping his bride.
Im trying to be okay with it, since it is after ours. However, I keep finding myself upset that we won't have something special to ourselves. Especially since half the guest list will be repeats at the same venue
am I crazy for being so frustrated by this?!
Re: Sister in law wants to use same Venue
I think you need to let this go; you and your FI get one wedding day, and so does your FBIL and FSIL (because that is what she will be, not just "his bride"). They are free to choose any venue they want for their wedding, and so are you, but you don't have any right to tell them they can, or can't, use a particular venue just because you got married there 6 months before they did. They don't need your permission to book a venue that works for them.
The only solution is for you is to buy this venue and shut it down immediately after your wedding so no one else can use it.
Any venue that is willing to host your wedding has every right to host weddings there whenever they wish, as they are a business. Think of it like this: be flattered that your FSIL loves the venue as much as you do. And even if she ends up decorating the venue the exact same way you do (which is highly unlikely), she'll be marrying her FI, not yours, so her wedding will be unique to her.
This is an excellent reminder to not sweat the small stuff. This is very, very small stuff. The only way this would become an issue is if she wanted to book the wedding there the same day as you, and somehow went over your head to steal your spot from the vendor.
Look at it this way, you have such great taste in venues that someone else wants the same one! Think of how wonderful it will be to return to the place that you were married and reminisce on your special day. Most people don't get a chance to return to their venue so that is something unique!
We got married in our favourite restaurant and I love that every time we return I think about our special day.
It was never her job to ask how you felt about it. Because frankly, where they get married is not your business, and you don't have veto power over their venue. Two of my cousins had their reception at the same venue a couple of years apart, and I promise you, no one thought less of either reception.
^^^ This is excellent advice. My DH and I were married in a botanic garden. We've been back many times since the wedding. We went on our six month anniversary, just for fun. We went for their July 4 festivities and fireworks. Now we take our kids there.
I think this issue can be addressed by adjusting your attitude. Instead of looking at it as losing something, see it as a chance to revisit a place that you obviously enjoy, and which is special to you.
This is kind of an attitude thing on your end. You can either be pouty about it or take the high road. The latter will make things easier on you and preserve the relationship, I promise.
On the plus side, their wedding is after yours not before. I just wouldn't continue to share wedding details with them for the rest of the planning process.
That venue exists because plenty of other people want to use it for their events.
You NEED to let this go.
Remember that no one will be as excited for your wedding as you are, and no one will find it as special as you do.
You'll be better off just letting it go. Saying anything will cause a major blowout. Your FSIL deserves to have her wedding wherever she would like, just the same as you do.
A friend's brother is getting married in the same venue she used AND like within a week of her anniversary. Guess what she and her husband are doing? Going to the wedding, and using that opportunity to reminisce. It's like having a birthday near a holiday or something. Double celebrations!!
Regardless, I agree with PPs- it will be nice to go back to where you were married, reminisce and enjoy the venue as a guest rather than being the center of focus at your own wedding. I had the opportunity to do this around the time of my first marriage. I chose the venue, only to meet someone and become good friends with them. Their venue canceled on them and they ended up booking my same venue and had their wedding before mine. I was glad I got to enjoy it because my wedding day was a total blur.
You need to let this go. You don't own the venue. Your wedding will still be special.
Your FSIL has every right to book any venue she wants for their special day and was under no obligation to get your approval. Plus, by the time they get married, you will be a six months married couple, who hopefully will be over the novelty of wedding planning.
My H's cousins who are from a small city all got married at the same church and had their receptions at the same venue. There were limited choices of venue, but there were choices, and they still all chose the same one. That didn't make us any less happy to celebrate them, or think their weddings were all the same, or that they were boring people. Different couples, different toasts, different marriages.
Don't be too caught up in being unique. Weddings are very hard to be "unique" about - there's really not much, if anything, you can do differently than everyone else who's ever been married, without veering into crazy territory. You'll get to be married, and people will be very happy to witness that milestone, because they care about you, not because they were caught up in a unique wedding experience you crafted.
And I would have been ecstatic to go back to my venue and enjoy another wedding there.
Everybody now!
But seriously, @ernursej gave great advice. DH and I would LOVE the chance to attend a wedding at the venue we used and reminisce on our wedding day. This is not something to get your panties in a wad over.
Here's a story for you... I wrote our wedding ceremony (with H's review and seal of approval) based on various things I found all over the 'net and readings and such. The judge (a friend of mine) who married us liked it so much that he decided to use it for ALL of his weddings! And my cousin liked our officiant so much, that she enlisted the services of the same judge for her wedding a few months after mine.
So there we are, at my cousin's wedding ceremony, and the judge (my judge) starts... and we're sitting there, listening to actual OUR WEDDING CEREMONY all over again, this time for my cousin and her now-husband.
You know what I did? I cried. Because I was so happy to hear our ceremony again and it made me all sentimental and sappy.
Going to the same venue? Enjoy it. Get sentimental and sappy.