Thank goodness! When I finally read the ingredients on that stuff, I was done with it for life!
There are wedding cake bakers who make a whipped cream frosting...it's not as problematic as some have experienced (though you wouldn't want to have that on your cake during a 100 degree August outdoor wedding...on the other hand, our lovely preservative-free, fresh, buttercream frosting did just fine despite our baker's concerns, during just such a wedding day). I only use fresh-made whipped cream now...do it right and it stands up beautifully, does NOT melt, and is delicious.
It's going to be the adding of the pudding that's the hard part though...fold it in gently, if you haven't already done it.