Yes, I know exactly what you mean unfortunately.
Although you are over the initial horrible anxiety attack stage, it sounds like you are still understandably experiencing severe anxiety/depression re the Tinnitus, like the feeling of being trapped in your body. I went through the same stage as well (I used to hit my head in frustration because I couldn't escape the noise).
It is a stage, and you will be able to overcome it and eventually leave the hospital. Antidepressants take about six weeks to have an effect, so you won't feel any improvement yet.
I think we all understand the frustration of being told by Doctors that it is the depression/anxiety we are feeling that is causing the Tinnitus, instead of the other way around. I guess they say this because they can usually treat depression much easier than Tinnitus. But
of course it is the Tinnitus that is causing the depression/anxiety - and it's a reasonable and normal reaction. However, the relationship is also cyclical - the depression/anxiety will be making the Tinnitus worse and causing the hopeless feeling, so please try to remember this. Once I had the depression/anxiety under control, I felt so much better.
Similar to you, I also have oscillating, morse code type Tinnitus, as well as some other sounds. I agree that the changeable nature of it is annoying! But over time, I have found it to be much, much less so. Sometimes I think of it and it annoys me, but mostly I don't.
Can your sound be masked by something like white noise or running water sounds, played on a laptop? Just knowing you can give yourself a little break from it if needed can make all the difference. If not, there is still plenty of hope. Many people go on to be able to completely ignore their Tinnitus with time - my Grandad has severe Tinnitus that he can hear over everything, and he will go whole months without even hearing it. When he first got it, he was suicidal. But now, it doesn't affect his life in the slightest. My friend had severe Tinnitus that eventually reduced drastically and can barely be heard now. There are lots of similar stories in the Success Stories section of this site.
It's not my area, but the Research section is full of hope right now for various different treatments. If you're science-y minded, you might want to take a look.
I so hope things improve for you soon. I'll say again: it's very common for Tinnitus to decrease, disappear or cease to be a problem, although it can take a long time. Don't give up hope