Depressed

My husband and I have been TTC for 18 months now we've been married for 3 years (he is 31 and i am 27) and just recently started seeing a doctor. When I told my parents we were going to the doctor my mom said "Are you Sure that's what you want? You do know this will change your life right?" My dad said " You're dumb for having kids. I don't need anymore grandkids. You won't be able to just pick up and leave whenever you want" my sister told me today she doesn't support my decision to go to the doctor because if God wanted me to have kids it would have happened naturally not from taking pills...I have no support from them and it sucks! It's so hard not to be depressed when you hear that from your own family...