What do you do when you get stabbed and an mip?

This is what happened. The other night I was at a bonfire, there were like 20 people there roughly. We were all having a good time when out of nowhere these 5 shady kids come out to it. Those 5 kids punched someone to the ground and all of them jumped him and just started kicking the crap out of him. It was dark and that happened away from the fire so nobody really knew what was going on until he came back to the fire all beat up. Everyone is about to leave at this point. We're all by the cars, talking about what happened to him, and this kid blindsided me and was on top of me punching. I couldn't really do anything, it was dark and I was so thrown off, so my friend got him off me and I started defending myself and he ran off somewhere. At that point me and my friend just wanted to leave so we got in his car. Just as the cars started and starting to take off slowly, I noticed someone running up to my window. My window was down (don't even ask why, idk) and as the cars moving he reached his arm in and stabbed at me five times. Luckily he only got me once in the arm, but if I didn't block it with my arm it could've gotten my ribs or heart. My friend rushed me to the hospital, and i had to get 6 stitches, and a few days later i had to have surgery so now its 20 stitches. After they stitched me up, a cop came in the room. The first thing he did was ask me to take a breathalizer. I refused, and why is that the first thing he asked? I got stabbed, and he wants me to take a breathalizer. After I told him all that happened, he gave me an m.i.p. I had court today and now im on bond because this is my 2nd mip, am gonna probably be on probation, have to pay all fines that come with it, AND my medical bill, all while the stabber is still out there. I gave the cop names and am waiting to hear something, but its not looking good. How is this fair? Any advice?