Having experienced mild depression--which is NOTHING near what the MLCer feels--yes, it is misery. But the depressed person has no idea they're depressed--it feels as though you've always been that way, that it's other people/things that fail to give you any pleasure any more. The depressed person has no idea she's unhappy and hurting--she just thinks that if she finds new activities/friends/lover (etc), she'll feel fine again. So seeking the trappings of a new life makes her seem enthusiastic, but that won't last.
It's not surprising that your wife couldn't follow through on her promises or decisions. Depression seriously affects the ability to make choices, the energy to accomplish things, the memory, and the ability to really care about anything. Believe me, she is hurting, if only at a level that she can't express to herself yet, and worse is to come.
