Yes I agree, we disagree on this topic, so be it
Like I said I see issues drawing parallels between single parent families and homosexual families, the dynamics and potential problems are quite different between the two. I am also going by current research which clearly demonstrates the issue you expect (and I would too logically) does not in fact exist. Perhaps those studies are incorrect or biased, but it certainly would not be the first time that psychological research has demonstrated that common knowledge is in fact wrong.
You certainly are correct regarding psychology and political correctness, though I would mention it has infected all of academia. People like to think it prevents biased thought, but quite often its the reverse and that it is in fact causing a bias. To me psychology is part art (philosophy) and part science, and constantly evolving. To be a good scientist one must attempt to remove oneself from all biases, and examine the gathered data with open eyes and not try to interpret the data in the way we want it to be, but rather how it is. In modern psychology's defense I would point out that far more experimentation is going on now then pure theorizing. Part of the reason why theory in psychology has changed so frequently is because a lot of the theories were not backed up by real evidence, or any experimentation (or invalid experimentation).
I myself have not abandoned psychology, though I do see some of the issues you mention. My only solution is to critically examine the research and see if the reasoning behind it is sound or not. Of course also psychological theory is never 100% and does not match with every individual, there will always be exceptions where the model doesn't fit. As for our original topic, I myself can rationalize children growing up happy and well adjusted in a homosexual family, as long as the two parents are good loving parents who support and take care of the child. It may not be the ideal situation, but when is there ever an ideal situation?
Anyhow with respect we must disagree as you say