This might not be at all what you want, but...when I was trying to lose weight after DS was born and I'd start getting discouraged, I'd tell myself, "I'm a lean, mean baby feeding machine!" and that would help me stay on the elliptical a bit longer. Since I started this pregnancy overweight and am worried about gaing ivermuch (but obviously don't want to diet) I've changed it to "I'm a lean, mean babymaking machine!" A litttle corny, but it seems to work for me, both for healthy eating and for exercise.
How about something like, "I trust that this pregnancy will unfold just the way it should." or "Baby, you are so wanted and loved. I am looking forward to meeting you when you are ready."
there was a thread a month or mor ago, either here or on the Nov 2010 DDC called "What if up" that talked about asking positive "What if...?" questions. Like, instead of asking, "What if this nausea never ends?" you ask "What if I get so much energy in the second trimester I'm able to get that remodel done??"
hope this helps.