I've had 3 D&Cs. The first 2 were in a hospital-which made it more of an event, but the drugs were better. The only advice I have from that is to make sure you have an order for more pain killers if you need them during recovery. The first time I didn't and it took a few minutes to reach my doctor to authorize more.
The most recent was in office by my OB. It was more uncomfortable than the hospital, but over quicker. But uncomfortable I mean that there are brief periods of intense crampiness, and they pass quickly. The hospital means registration, pre-op, recovery, etc before you get to go home. At the OBs it was over in less than an hour (from car door to car door, the procedure took maybe 15-20 minutes). As soon as I could stand up and felt okay they let me go home.
If you can bring some portable music player with some relaxing music I would do that. I won't tell you that surgery is without risk, but it is true that our perception of those risks is out of proportion. Getting in your car is one of the most dangerous things you can do, but we all do it all the time. Unfortunately they have to do this all the time and the complication rate is very low.
I also feel like their is a lot of weirdness around D&Cs because of the anti-abortion folks. If you watch TV you'd think everyone who has a D&C winds up infertile later, or has horrible problems, and it's not true.
Be prepared for some period like discomfort afterward, and you'll want to drink more liquids, and eat more protein both before and afterward. If you have a place that sells homeopathic remedies, you can get arnica tablets and take them before and after. This will help your body deal with the inflamation and help you heal faster.
It's the most natural thing in the world to be nervous about surgery, but the actual event is not as bad as the nervousness.
I also think that you are being very responsible by weighing your own needs and responsibilities and making the best choice for you. It's different for all of us, and different for each of us at different times. Please PM if you have questions I didn't answer or anything I said is unclear.