PTSD along with pre-existing depression/anxiety!?

I have to agree with you that professional help is needed, whether your parents agree with you or not. Your first stop may be the universities health center or even their website to see if they have a counseling center. If anything you can have a consultation with one of their counselors who can refer you to an outside practitioner if they agree it is needed. I have been diagnosed with PTSD and honestly the thing that works best for me is being in therapy and also trying to take things in my life one at a time. While I am long past being in college I remember how overwhelmed I used to get not only with the academic aspects of things but also the social issues and dealing with family issues. I tried to tackle everything at once and found myself paralyzed by everything. When I was able (with the help of a counselor) to break things down and set some shorter term goals that were easily attainable I was able to cope better. When it comes to dealing with the PTSD I was once in a group held through a local crime victims service which had a support group for trauma survivors. If your suicidal thoughts become overwhelming and you are at risk for attempting suicide get yourself to the nearest emergency room. Your life is way too valuable to go down that way. Honestly it is. If I can be of any help you to please let me know. I wish you luck.