Remember in life that the success to a happy baby is a happy you. Don't allow anyone to alter who you are or negative happenings around you during your pregnancy.
During your pregnancy not everyone has to know. Tell only those who you want to know. Those who you think won't handle it well-well let them find out later. Your emotions are the most important involved in your pregnancy. If your baby detects throughout your carrying him/her/them, then they will possibly grow up to be the miserable person you were during that time.
Your mental stability can alter, change or determine your growing baby's stability. Make your pregnancy a happy one and make your baby the same.