She’s always better than me in everyone’s eyes she always is better than me at everything!
This applies to a lot of people who mog you, why single her out?
Take a broader view of society OP don't just focus on people proximal to you like pathetic normies.
She engaged now and everytime she talks about her getting married soon and how happy she is it pisses me off like why wasn’t my life like hers!!
You want to get engaged to her BF? Sounds kinda gay OP
she makes fun of me and shit and always says how odd I am
You are odd. We're all odd here. She's correct. Pretty lite insult there.
If she said more serious stuff you should focus on that.
and I’ve heard her whisper to her fiancé shit like “my brother is kind of An asshole”
Perhaps you should talk to her privately sometime and say something like this.
"Sister, I overhead you said that sometimes I am kind of an asshole."
"I am trying to improve my behavior towards others."
"Would you give me some advice on how I can treat you better?"
Try to seem genuine about this, see how she talks. Might be interesting to observe her reaction to this.
If she wants to think of herself as a non-asshole then she needs to indulge your cry for help.
Or you might just find out she's embraced hypocrisy and doesn't actually believe what she says to others.
my sister thinks I’m weird and gross and almost never talks to me unless she needs something
We are all weird in here, it's okay for you to think that.
If she ever calls you that, you should just embrace the term.
"Hey sis, I know you think I'm weird, and you are correct, I do have a lot of unusual interests."
"But I hope you can see I at least have the potential to develope some good interests."
"Are there any interests in your life that I could share with you?"
"Maybe we could go shopping together and talk?"
IE exploit her being willing to interact with you when she needs something and use it as an opportunity to converse with her.
Tell us what happens if you do this OP
also she had a breakdown once a few years ago and broke my houses (technically my parents house) window with a baseball bat
Did she get locked out or something and try to break in, or did she smash the window from inside the house?
What prompted the breakdown?
and then cried on the floor
Dude that's sad you should have given her headpats after hiding the bat and sweeping up that glass.
If you're a responsible bro like that maybe she will give you cuddles later.
but The one time I tried to rope and failed like a pussy and went to the psych ward nobody really gave a fuck
They might have cared, just to a lesser degree.
People also have different more stoic responses to male suffering compared to how they will coddle female suffering.
..whatever I’m rambling what I’m getting at is that I fucking hate my sister I used to look up to her as a kid now I just fucking hate her and feel jealous
Let's look back a bit OP.
When you looked up to her, what traits about her did you admire?
Does she still have echoes of those traits even if they diminished?
I understand what it's like to get caught up in feelings of jealousy about family members who seem to be getting preferential treatment.
But a lot of the time the problem there isn't the person getting the preferential treatment, but the bias of the people doling it out.
You don't seem to be focusing on it actually being the fault of your parents for ignoring you.
If your parents ignore your suicide attempt, that's on them, not on your sis.
Have you recently made any attempts to connect or bond with her?
I wonder if maybe you did in the past and got shot down and gave up on future attempts as a result.
If you're feeling fixated on her and can't put her behind her, then you should at least be making attempts to reach out and reframe your relationship with her.
Otherwise maybe just give up on it and try to distance yourself so you don't fixate on the shit he does.
Also if this comes across as "holier than thou" I will also note that I am a hypocrite and haven't taken efforts I ought to have to distance myself from toxic people who haven't reformed their behaviors. I'm basically hoping you'll have more success than me, and your success will serve to inspire me.