I'm really depressed..?

It feels like my life has been holding everything in and now it's just crashing down. I'm only 13 ( 14 in two months ) and I've been suicidal so many times throughout the last year. I've been traumatized my entire life and we're going through a tough time with money right now to the point where we can't even afford to have a car. I'm also made fun of a lot and people put me down for no reason. I'm not fat, I'm not ugly, I'm not a freak. I keep to myself all of the time and now I feel so distant from the world. I don't want to hang out with my friends and I don't want to hang out with my family or go to work or talk to anyone. I feel like I'm the outcast in this world. Nobody understands me and I'm too afraid to tell my mom about my problems. I'm Catholic and since I've been suicidal and i've been cutting I feel like I've betrayed God and it's just making me more upset. The only reason I get up every morning and continue to drag myself through this is because I don't want anyone worrying and I want everyone else to be happy. My self esteem is extremely low and I feel so helpless. I've asked God to help me so many times and I've prayed for his forgiveness so many times but the guilt won't subside and its just making me spiral deeper into my depression. I like cutting because it makes me feel somewhat better and less stressed but afterwards it just makes everything worse. I just want to break down and die. What should I do about this? Spending time with others is the last thing I want to do.. And I have to go to a friend's birthday party tomorrow and I'll have to act remotely happy and interested. Also any suggestions on hiding my scars and cuts? I don't want her worrying about me either. I've already confessed my cutting problem to a few of my best friends so I feel like I'm not completely and utterly alone. I really don't want to tell my mom either.