Your sister has been there since you first started dating, and has never failed to offer up her honest opinion. When you finally settle on the person you think is perfect for you and your sister doesn't really like them, it's devastating AF. It might not seem apparent at first either, because you're used to her getting along with everyone, but those signs your sister doesn't like your SO will catch up to you sooner or later.
You would never choose sides, because that's so elementary school and she's too dope to ever make you do that. But if you're close to her, you will peep the changes in her behavior. And because she would never want to strip you of something that makes you happy, she has likely been reluctant to bring her grievances up to you. Yeah, she's pretty selfless as hell.
A relationship should never shatter or break your sisterhood, but coping with your sister not liking your SO is tough. Again, you might not know at first because outing you for something that's not your fault isn't her style. Sadly, it might be more of a suffering in silence thing early on, but you can catch on if your sis is doing most or all of these things.
Your sister doesn't like to be a Debbie downer, so she might rather not attend family outings with your SO there. It's better than putting so much energy into dodging them and making the situation awkward around your family and close friends. Those outings really aren't the same without her there, though.
Your sister used to be at your place all of the time, but now that you live with your SO, things have changed. Anytime you guys want to stay in and hang out, she always recommends that you do it at her place. This should really be a red flag that she is dodging a specific someone or thing associated with your place...and it's not you.
You know your sister's personality and the way she interacts with people when you two are together. If she consistently retracts herself from the situation every time your SO is around, she's clearly not comfortable around them. Think of it as your sister, the social butterfly, regressing back into a caterpillar cocoon because of who you're with.
Normally, your sister is open to any giving advice, listening to your venting, or just receiving an update about your life. But when you start talking about the person you're getting serious with and she immediately seems disinterested and changes the subject, it's bad news. It is not like her to brush over a potentially hours-long subject with you. She lives for those convos.
When someone gives you the "whatever makes you happy speech", it usually means they feel completely incapable of changing your mind and don't want to infringe. It's appreciated, but your sister's happiness is also a component to your happiness. The idea that she is giving you this speech, should set off a light bulb real quick.
Usually, if you and your sister are dating someone special at the same time, you have a backlog of double date ideas you want to do. Unfortunately, you're the only one daydreaming about them because your sis has already counted her and her partner out. She would never turn down a double date with you, so something must really be going on.
Of course, many of your traditions you have with your sister will remain between you two. As far as the ones that have a little more leniency, she hasn't even brought up the idea of including your SO. Those traditions have always warranted fun and memories, but she clearly isn't trying to make any with your SO.
Make sure you're peeping all of the signs that your sister doesn't like your SO. She isn't always right, but when it comes to you, she's always looking out for what's best.
