These girls are totally right! We're spending about double, for double the guests (this is also accounting for everything). The good thing is that with that amount of guests you have a lot more choices in resorts, and for many you can use their free wedding packages and upgrade a few things only. That really helps with keeping costs down.
Just don't get sucked into pinterest weddings! hahah, worst thing that happened to me
Sometimes it is really the vendors that take up a whole chunk of your budget, for example between photographer and Dj you could be looking at 2-3K just for that. Then you have to start prioritizing and maybe, for example not hire a DJ (this is what we did), or hiring a photographer for less hours rather than the whole day, etc.
Also, be aware of unexpected expenses and plan for that, so if you really don't want to spend more than $7000, aim to keep your wedding at $6000 and have $1000 of cushioning just in case. For example, for us, the Canadian dollar went downhill in the middle of the planning and now we need to take that into account.
Overall, I definitely think you can work with that budget though. As I always tell people, you can always work with any budget! It's only a matter of what you want and expect for this wedding and of course, the smaller the budget, the more cuts you might have to make on certain things, but it's still doable . The most important thing, after you set your budget, create a priority list. It will help to keep things in perspective.