Good for you for making this choice
I just completed 30 days in a rehab facility and not only was it outstandingly helpful, but I thoroughly enjoyed my time there. It wasn't a lock down unit, we were able to have phones and laptops and all that which was something I was not expecting; not sure if your program will be similar in that regard.
I made the choice to go because I knew I could not stop on my own, and a simple 4-5 day detox (my 10th, I think) was not going to cut it. I needed far more support than that and at the facility I went to, I received it. This may sound bizarre, but I think I'll always look back fondly at my time there.
Keep us posted, and best of luck to you