Okay. I think I can claim "expertise" on the matter since I've been sent away a dozen times. Literally--12 times into the mental ward at our local hospital since 2002. Average stay was 10 days each. Anyway, my doc would put me there if I posed a threat to myself or others. If I was having ideations, he would watch me closely.
Now, there's different types of being committed. One is voluntarily, which is the category I fell under. Honestly, I felt pressured because my doctor would've fired me if I didn't go, but I could've left at anytime ADA (against doctor's advice), but would not be welcome again if I needed to be there in the future. So, they say it's voluntary, but it's kinda not.
The other type is when there is a court order issued for your committment. For this type, you are usually brought into the hospital in handcuffs. This method is resorted for those who absolutely have to go in but will not cooperate. Any doctor or family member can have you court ordered to be committed if they deem necessary. This does, however, lead to a longer stay AND, in my state, send you eventually to the county mental facility when a bed opens up. That stay is usually not too long. Kinda pointless if you ask me. Total time of committment in this case is over a month.
Being hospitalized for mental illness is anything but a vacation. You lose all your rights... especially if you are under suicide watch. When you come in, you lose your shoelaces, your belt, and all your toiletries. You have no mirror, no coat hangers, no racks. You can only shower at a certain time, which is the only time you can have your toiletries. If you want to shave, you must wait until things are going slow so a tech or nurse can be there to watch you. You have to conform to their schedule and one community television. There's awful, boring activities and group therapy about 4 times a day, except weekends when you do nothing except count ceiling tiles. If you get in trouble, you may get sent to solitary confinement. If you get out of control, they can stick you with a shot that will knock you out for 2 days. Straight jackets are rarely used and they rarely ever strap someone down unless it's absolutely necessary. There's no privacy, total boredom, and the ups and downs that go with medication changes. You only get to see your family for an hour in the evenings and twice per day on the weekend. It's awful. Thankfully, it's a place I haven't been to in 2 years. At one time, I was deemed a "frequent flier," as they called it. AWFUL... (Oh, and limited caffeine, snacks, and awful hospital food. I always lost weight and then they would try to tell me I was anorexic. What a nightmare...)
With that said, you still really NEED to confide your feelings to your doctor. If you can convince him that you are not a threat to yourself or others, you should have nothing to worry about. If he feels you are a threat, he may resort to having your family watch you closely before considering hospitalization. Depends on the doctor and the level of care in your town. If you go, I sure hope it's better than the place I ended up. I've heard ours is worse than average. They don't even allow people to smoke. Smokers have to wear a nic patch, so they are all just pissed off the whole time and can't work on getting well because they're just pissed 'cause they want to smoke. I felt sorry for them.
Now I have a new doctor. The other one did eventually fire me. I think my problem was the old doctor. I've been fine since my new doc pulled me off of half the meds I was on. Turns out, I was overmedicated. I feel pretty okay now.
Good luck to you and I hope you are feeling better.