So, I feel like my positive affirmations always take place in my prayers. I try to pray (casually) whenever I lay down or whenever my mind wanders... I say things like - Thank you for this healthy pregnancy, my healthy son and my healthy husband. Thank you for choosing me to carry this life inside of me. Every sign that I have that may not make me feel well, this is You showing me that my baby is happy and healthy inside of me. Please help me to remember this and have more patience with how I'm feeling, with my son and with my husband, and also with myself for not being able to be as productive as I'd like to be. Amen
I feel like something like this would work even if you're not a spiritual person - you could be thanking nature and the support system you have.
Has anyone ever read what Waldorf teaches to the children about how they came earthside? I love this picture in my own head... [I'm paraphrasing from how I understand it] All of our babies are angels up in heaven where they are having this beautiful time. Then, it comes time for them to leave heaven, but the choice is theirs on who they want to be their mama and papa. So, they watch us from above and when they find the perfect match, then their mother becomes pregnant with that special spirit. When the kids have a birthday in a Waldorf school, they get to walk on the rainbow silks and tell the story from their perspective about how they chose their parents (at least from my friend's whose children have attended Waldorf have had this experience). I think this is beautiful - and what we should all be reminded of even on our worst days, when we feel like a bad mother, a bad partner, a struggling homemaker/friend (fill in the blank) - we were chosen to have this miracle of life inside of us. That spirit inside of you knew that you were the best possible person that he/she could ever be blessed with to have as a parent. So, we should try not to be too hard on ourselves!
Wow - a lot of rambling... However, I am a HUGE believer in positive thoughts = positive outcomes. (It can't hurt, right?!) 
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