I Am So Upset,mad,angry At My Sister

I am writing this because I am so stressed and frustrated with my life and I need to releases them somewhere...

I would do anything for my family. I would like to give anything and protect each of them as much as I can. We have happy times and rough times and I don't think I can take it if anything bad happens to them. I'm the type of person who can catch a bullet or die for them. I'm 22 and I have a stable but low paying job and I am frustrated because of that. My parents always lived in poverty and I want them to have the best things in the world, now that they are getting older. I have a sister who is about 2 years older than me, and my parents did everything just to get her to one of the best school. After she graduated, my parents also did everything so that they can financially support her so that she can go to Europe to get a job (with the help of their rich siblings, my aunts and uncles).

Back then, she was like me, she wants our family not just to have good , but the very best. She had plans to get our family our own house, because we live in a borrowed small house in the suburb, she had plans to take the whole family to travel, and my mom's operation and all that. But when she got into a relationship with a guy for 2 years, everything changed. She no longer wants to support my parents, talks back and says crap about our relatives who actually helped her to go to a good school and supported her so that she is where is now (to the point that she no longer talks to them and even blocked them to social media).

As their relationship progresses, I just observed that she is obsessed with him to the point that she is actually supporting his boyfriend while she is working in Europe and even financially supporting him so they could travel, while we are out here struggling how we can get through the month because of all these bills to pay. Also, to the point that she talks more to his boyfriend than to her own family. I wish I could support my family on my own, but I just graduated and am still struggling to get through my job and Im earning too little.

I know I will get a lot of hate because people will say "it's her money she can do anything with it" but for me it's not right knowing damn well that my parents did everything just for her to study and get a nice paying job. Now we got to an argument because she said she no longer wants to support our family because she wants to marry his boyfriend.

I love my sister and she is to me my best friend and will support her happiness but I just can't help to get upset and be angry at what she said. She traded her dreams back then of getting my parents a good life over his stupid ass unemployed boyfriend who she only had been with for 2 years. I personally do not like the guy for him for many reasons but if that's who she want to be with that's fine, but for me she should give something back to our parents.

EDIT: Now I am not trying to write this because I am the best kid in the family. I am also a bad kid. I just can't help to be upset because we used to dream together for the best of our family...

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