This isn't what you really want to hear, but you can function quite well with only one ear...once you get used to it. Worst problem is that you can never figure out where sound is coming from, which leads to lots of exercise for your neck muscles as you swivel your head around. I once was walking on a city street with a friend who also can't hear on one side, when a fire truck was a couple of blocks away. We caught each other swiveling our heads around in an attempt to determine where the siren was coming from...and almost fell over we laughed so hard.
The noise is tinnitus, which is nature's way of giving you something to hear. Yeah, it's definitely NOT what you want to hear, but it is intended to fill the void. I refer to it as my "radio station from hell." A hearing aid brings in useful sound (if that ear is "aidable") so that the tinnitus is far less bothersome. Over time, you also really do get used to it. I don't even notice it until someone mentions it. I've had no useful hearing in my right ear for over 30 years.
If you have even a small amount of hearing (not necessarily discernable by you), the left ear may be aidable. I found that the audiologist at Costco has been extremely helpful and able to adjust my one aid to maximize what I can hear, and Costco aids cost far less. I have a Bernefon Zerena, which is made by Oticon, has accessories available, and is designed to be paired with an IPhone (conversation is delivered directly into your ear). The audiologist I've seen at the CI doc's office gives Costco high marks, BTW.
If you have hearing in your right ear, you may not qualify for an implant. I just went through the testing and got a 55% grade, which means that I can hear a bit more than half of simple sentences in a sound booth--50% is the level necessary for an implant. To help you learn to maximize what you hear, you can do exercises in listening at angelsound.com. There are no lip reading (now called speech reading) classes in the US, but you can buy a manual online from Amazon: Learn to Lipread by Virginia McKinney. I'm working on the listening exercises, but haven't yet received the book (just heard about it).
You will need to position yourself so that your hearing ear is always toward the sound you want to hear. Because you can't hear on the left side, you'll always want to be on the left side of the speaker, the auditorium, etc. As you age, you may need an aid for your good ear (age-related deafness), and, eventually, you may well qualify for a CI. One good thing is that, unlike organ transplants, really old people can qualify for CIs. Another good thing is that technology is moving quickly to produce better aids, better accessories, etc.
It's really dark for you right now, but it will get better. It's a terrible shock when it happens; it takes some time to get used to. Good luck!
Thank you for this information. Lost hearing in left ear suddenly 4 yeas ago. Went through all treatments suggested and acupuncture. Nothing helped. It is as it has been described above. I think i have started lip reading but i also just tell everyone i meet so they will understand. I do neck exercises because it sure does get a work out.