How do I help a college friend who might have ADHD?

[Person]

I think 1 of my really close friends has ADHD. Its really affecting her grades. We're in our 2nd semester, going through exams; she's not doing well at all & is having really low self-esteem. She's studying a lot, but doing bad cuz she's having problems concentrating. She's being really sensitive about her marks, she's being calm (unusual) and getting depressed. She got a 2 (point something--like 4) GPA last semester and is really upset. I read the symptoms & think she has it.
Her family doesn't have any medical or health background so neither she or they will understand what ADHD is, and she'll take it offensively, like "you need a psychiatrist".. I'm really sure they won't understand, but I really think she needs help. I want to help her, she's going through really bad times now and is getting emotional, but I'm not knowing what to do. Her mood and negative attitude is really affecting our friendship, and she's usually a really fun type of person and all, one who I really cherish.