I'm so sorry to hear about what all you are going through. I think it's great that you are willing to go to inpatient to help yourself. Inpatient can be scary at first, but once you get to know everyone and know your way around, it get's easier. Try to go in with a positive attitude about wanting to get better. It helps a lot. As for what to expect, generally there is group therapy (usually a lot of different groups through the day). You may also see an individual therapist or social worker. You will probably meet with a treatment team, including a psychiatrist so they can evaluate you and figure out how best to help you and how long you will need to stay. They may put you on or adjust your meds if you are on any. The longest I have had to stay was two weeks. I've been in inpatient I think 8 times now. I would recommend bringing some books or magazines or something to help keep you busy during the off times (like when no groups, or anything) because sometimes it can be pretty boring in there. I also like to bring a comfort item (like a teddy bear) to cuddle with at night. There are nurses around all the time, and if you need to talk to them, you can. You may have your own room or you might have a roommate. I have been to a few different hospitals and a lot of things can very, but hopefully some of this will help you to prepare.
Wishing you all the best!
~Angel