I'm sorry you're going through a rough time but glad you're attempting to get sober.
Reminds me of something my sponsor told me. She was pulled over one afternoon for speeding. She was sure the cop would notice she was in a drunken stupor and she'd be hauled off to jail. Some how, the cop didn't notice. She got off with a warning and made her way home.
She thought to herself. Wow, that was a close call, I've got to stop driving. She says it didn't occur to her at the time that the drinking was the problem, not the driving.
You're story about quitting rehab because of the shame and embarrassment made me think of this. You're ashamed, not because you're in rehab but because you keep drinking. I would suggest you think about that decision a little more.
If you want to get sober and make a better life for yourself it will take some sacrafice on your part. It did for me and it's paid off ten-fold.
I went to inpatient treatment and was worried about telling my boss as well. I know how it feels, it's not easy. I was at a point that I knew if I didn't do this to get well I wouldn't have a job for much longer anyway. Heck, he wasn't even surprised, he knew something was wrong. I was giving a full 10% at work each day, if I chose to show up.
The fear of telling him lasted a very short time and after I did ..... instant relief. It felt nice to be honest about myself for once.
I tell you all of this to may be make you think and to let you know that you are not alone. So many people have been through hell and back and we're able to get sober. It is possible for you too.