Sugar-free gelatin with whipped cream is OK, but there are a few warnings. The SF Jello brand gelatin is made with aspartame, which many people avoid because of stalling and the bad health effects. You can make your own SF gelatin with Splenda or DaVinci syrups — search the recipe section here for ideas. There are also some brand-name gelatins made with Splenda. Ready-made Jolly Rancher is an example, if I remember correctly. Regardless, read labels. Some people have a problem with aspartame, but I do eat SF Jello brand every once in a while with no problems. Also (geez, this is getting longer than I planned on!) make sure you're using real whipped cream that you whipped yourself. The stuff that comes in a can or a tub contains added sugar.

Next question: Cream cheese. If you buy Philadelphia in the 8-ounce blocks, it's premarked on the foil by the ounce, kind of like how butter is. Looks to be maybe 2 T of cream cheese to an ounce, but don't take my word for that.

Lastly, Baker's unsweetened chocolate. I use this to make homemade peanut butter cups (absolutely delicious, by the way) with no ill effects. It probably does contain some natural sugar, but in small enough amounts that it's never bothered me. And hey, there's new research out now that suggests that chocolate is actually good for us — what do you know!