He certainly viewed his would-be sweetheart as more of a mother figure than an actual spouse or what have you. However, I think at that time he genuinely wanted a surrogate for Barb who would take care of him after the deaths of Barb and Bob. I don't believe he actually wanted to have sex with Barb or be in a relationship with Barb at that time. What's interesting, in light of all this, is that Barb is likely the person who originally put the idea in his head that his future spouse should essentially be Barb 2.0. And even if she didn't play a crucial role in constructing the idea of his sweetheart, she doesn't seem to have made any attempts to correct his vision of an ideal mate.