My (29M) GF (27F) of 3 years cheated on me with my brother (27M). My family is siding with them.

Despite my desire to shame them publicly, I will use fake names. Also english is not my first language so sorry for any error.

I (29M) have a younger brother, Gabriel (27M). Until a couple of months ago, I would have described him as a people person, someone who make up for his lack of skills with his great eloquence and ability to read people. Now I would describe him as a devil with a silver tongue.

While growing up, I have sheltered him from any kind of problem. Bullies picked up on him? I made them stop. He struggled in math? I spent hours helping him understand how to solve every exercise.

My parents are good people, they were strict with me but helped whenever I was in need, as long as they saw I was trying ( for example: for my first car, I worked in order to buy it. Once I made enough money to pay half of it, they paid the other half). Despite that, it was clear that Gabriel was always the favorite one ( same context: the car. When Gabriel turned 18 and got his driver license, they bought him a car. He never had to work for it.).

This favoritism toward him only grew stronger once I went to college. I decided to study computer engineering. My parents are old fashioned and don't understand what a computer engineer's job is. To them, I play video games from dawn to dusk. ( their words, not mine). I tried multiple times to explain to them what I do but it's like talking to a wall.

My brother studied business. Once he graduated, he started searching for a job. The company I was ( and still am) working for was hiring people so I told him, he got the job and now he works in the sales department.

3 years ago I started dating Chelsea (27F). We dated for 3 years and after a couple of months I presented her my whole family. She and my brother got along but I never thought anything about it.

Fast forward to 1 year ago. My department was short on staff. There was a recession, people were let go and that put even more work on my and my colleagues' shoulders. For 2 months, more or less, I worked from 7 AM to 5PM, then crawled home and basically fell asleep instantly. Even during the weekends, I was too tired to do anything special. This caused me and Chelsea to not be able to meet each other as much as usual ( normally we would go out at least twice a week. During those 2 months, we went out 1 a week or once every 2 weeks).

After those 2 months ended, things went back to normal, or so I thought. I noticed that Chelsea was distant even while we were together and her behavior was weird. She became quite possessive with her phone, she would suddenly cancel our dates and other things like that.

Anyway, fast forward to 3 months ago and I found out Chelsea had been cheating on me with my brother ( yeah, I looked through her phone, it's a violation of her privacy, I know. ).

I think I have never been so angry in my whole life. I kicked her out, went to my brother's house and confronted him. He laughed in my face. This man, my own brother, stole my GF after everything I did for him and even laughed in my face.

Not reacting violently in that moment was the biggest test of self-restraint I ever had.

I told him I had no brother from that moment onward and to act accordingly.

I got out, called our parents and told them what happened. They seemed to understand and said they would talk to Gabriel.

The next few months I was a mess emotionally so I tried focusing on my job.

I recently went to a family dinner and to my surprise, both Gabriel and Chelsea were there. To sum it up ( this post is already too long, sorry about that), my family decided to side with Gabriel, because apparently he and Chelsea " found their true love in each other and, while they hurt me, I should try to forgive them and accept it.". I told them exactly what I said to Gabriel: from now, act as if I don't exist.

They have been storming my phone with calls ever since.

TLDR: my GF cheated on me with my brother. My family is on their side.