In a large bowl, beat cream cheese with an electric mixer on medium speed until smooth and fluffy. Add Splenda sweetened condensed milk and vanilla, beating until fully combined and mixture is creamy.
Pour in milk and packages of pudding mix. Beat for 2 minutes, until mixture thickens to a creamy pudding consistency. Fold in 4 ounces of the whipped topping.
To assemble:
Place half of the sugar-free vanilla wafers in a layer on the bottom of a casserole or trifle dish. Next, add a single layer of sliced bananas. Then, spread half of the pudding mixture over the bananas.
Continue with one more layer: Sugar-free vanilla wafers, sliced bananas, then pudding mixture.
Garnish by adding the rest of the whipped topping to the center of the dessert. Sprinkle some of the wafer crumbs and a couple of sliced bananas on top. Cover with plastic wrap and refrigerate for at least one to two hours before serving so it can thicken up and the wafers can soften.