My boyfriend of 5 years went to my little sister 5 weeks ago, and told her he’s proposing. He brainstormed with her on a nice way to ask my parents etc. 2 weeks ago, I walk into my mother’s, and my sister’s boyfriend is there awkwardly, and spills the beans that now he’s proposing to my sister too! (He didn’t want me to know, I inconveniently walked in).
I’m upset because my sister has absolutely no idea, and innocently was telling her bf about my bf’s plans and he decided to sprint ahead and get to my parents first, two days ahead of my bf!
I find it really upsetting, is this wrong? My mother doesn’t get what he’s thinking, he literally has taken all my bf’s ideas for everything that he was doing, as my sister was naively telling him my bf’s plans! I never would think I’d be upset by something like this.
LemonVibe 
Well, it’s a shame he wasn’t thoughtful enough to let you guys have the lime light, but try to forgive him. I know that is hard since he seems to be narcissistic and self centered, but you’re not marrying him. Your sister may not even marry him in the long run, but if she does you’re going to have to deal with him at family events and so will hopefully be the bigger person. Especially since she’s probably going to need your help when he does something else crummy.
Take a deep breath. Marriage isn’t really a goal to check off. It’s a (hopefully) lifetime partnership. You haven’t even set a date yet with your boyfriend or gotten into any of the rough stuff yet. You are (rightfully) mad that he stole your boyfriends thunder. He really should be the mad one, and even if he is then what? Do you want a apology from your soon to be brother in law? Will you be less angry?
I guess in the future both of you should keep your special plans to yourself if you don’t want him to steal the plan and make sure his new fence/wife keeps him from photobombing you at your wedding.
Congratulations on your upcoming nuptials! Remember all this will pass. Don’t go bridezilla on people and you’ll be just as married at the end of the day after the wedding.