My parents dont appreciate me?

I'm 12, so I haven't had a lot of life experience. I know. And I know that I'm becoming a teenager and my parents are trying to cope with their baby girl growing up. The problem is, I attempted suicide and had to go to the hospital for 5 days. After I came back, all my mom does is yell at me and all my dad does is put me down. My older brother, who is 18 and the only boy, gets everything he wants. An iPad, laptop, car, money, everything. And my sister, whose 32, is constantly praised and she's my parents' world. But I don't get it. They just seem to dislike me a lot.. My dad is really sick and my mom works at night. My mom complains about everything that doesn't suit her fancy and my dad gets mad every time something doesn't go his way. They constantly put me down and comment about my weight and my binge eating problems. So does my brother, but I always get in trouble for his comments. Why do they not appreciate anything I do?