Sunshine--
I find it odd and interesting that even though your parents sent you to a professional for their assessment, they never sought actual TREATMENT for what you were diagnosed with (ADHD).
This is sad, because ADHD is very treatable, and untreated ADHD can easily lead to depression and anxiety problems as an adult. One thing I should congratulate you for though is completing college and getting accepted to graduate school without any help for the ADHD. Your situation only further highlights the fact that it is NOT just academics that are affected by ADHD, but also other areas of life as well.
Do you have health insurance? You might be covered by your parents if you do not have any of your own. The best thing to do is to see a therapist who has experience in treating adults with ADHD. Some are more skilled in this area than others, and you'll only know by contacting them in the phonebook for your area. A therapist with an MA or PhD in some sort of counseling field will be able to assess you and help you get treatment.
I find that medication works best with therapy. Some people do medication alone, and others don't use medication at all. Having a lifetime of the affects of ADHD can really take it's toll; even with medicine ADHD will not go completely away. Talk therapy really helps to deal with the myriad of issues an adult with ADHD is faced with.
What's stopping you from seeing a professional to help you sort out these things? Hesitation is normal, but most people feel really relieved when they start getting help with ADHD and whatever their other issues are.