Hi Chloebaby,
Having to leave your boyfriend and kids must be a very scary thing, especially without being able to talk with them. I think most rehabs have these policies to allow patients to focus on themselves with greater intensity. Maybe viewing it that way might help - the time you spend apart now will be reinvested in the future. Becoming sober allows us to give so much more time and attention to our loved ones.
I'm sure the idea of leaving home and going to rehab is a scary one for lots of reasons. It's totally fine to feel cautious, curious, afraid. The trouble is in not letting our feelings trap us in inaction. I encourage you to try it and wish you all the best.