Can Birth Control Pills Cause Attitude And Mental Changes?

My wife and I have been having marital problems since the birth of our second child. At first I thought it was me (I was suffering from depression) but after assesing the past few months and controlling my depression I noticed that the greatest change in her attitude was a few weeks after changing her birth control (the other pill made her gain a few pounds). We've been miserable for 7 weeks and she switched birth control about 11 weeks ago. Is it possible that her pills made her fall out of love with me and are they keeping her from accepting the new improved me?