My brain is fried

My 22M sister had a baby. I went to the hospital to see her. She had a huge smile on her face and was so happy. She had a girl. I'm so happy for her. I went to her house to check on her and her baby. And the first thing I noticed was that my brother in law never stopped fucking smiling. Like his face lit up every time he looked at my sister and his baby. Like he was the happiest man alive. I can't believe it. I have worked so hard to make it in this life. I'm 26 with a good job and I can't even find a gf. Like I got accepted to medical school. But I still can't find anyone. I just want to be happy and be loved. Like why does my sister deserve happiness and not me. I know she never got hurt in her life. She's so innocent. I can't believe she's a mother. Like she went from a girl to a mother. When I'm still the boy that I was. Like my life sucks. I have nothing. Like I'm just alone. I don't have a family. I'm not good. I'm so jealous of my brother in law I wish I could get some happiness