I understand your concerns and offer the following thoughts for you to consider regarding your decision.
1) When I developed tinnitus earlier this year, it is accurate to say that I was devastated and deeply questioning my path forward. I am a biological researcher with a PhD. I work for a university and my daily work requires maximum focus and mental agility. I can say that despite how new these tinnitus symptoms are in my life, I have been able to produce some of my best work yet while experiencing the symptoms. I had a few months during which I was too anxious to do much work, but after I decided I would not let this control my life, I am relatively OK.
2) A former employer of mine had painful ulcerative colitis prior to developing colon cancer, and eventually having his colon removed. His doctor told him early on that you can let this condition control you, or decide to take control of it. Easy to say...not easy to do. I think the connection here, and the reason I bring it up, is because we have the choice of making the most of our lives despite the biological imperfections that we all experience in some manner or another. Since I am a biologist, I take stock in the fact that Darwin reportedly had lifelong tinnitus, and the eminent contemporary biologist E.O. Wilson was blinded in one eye before conducting his most legendary field research.
3) As many war veterans pursue college on the GI bill after service, and tinnitus is a highly common condition among veterans, you certainly would not be alone as a college student with tinnitus. And if tinnitus were to impede your learning, you can and should take advantage of the disability services that exist on every college campus (in the USA, anyhow).
4) I subscribe to the concept that aiding brain growth (generation of new neurons and synapses) is one way out of auditory disorders like tinnitus. Since learning is one of the best ways to stimulate brain growth, you could view your decision to go to college as a way to aid your healing process.
5) Finally, plenty of research exists showing that tinnitus commonly resolves itself. It is unremarkable that this is the case considering that the body is constantly healing itself. It is likely that you will have moved past this hard time one year from now. The question is: what path do you want to be on next year, one of dwelling on an upset in your life, or a path of moving forward with your life's goals?
I wish you the best!