Congratulations on your pregnancy.
If I was you I would just stand up for yourself and say 'It's my baby, my pregnancy and I am handling the situation how I feel is the best way too'. Let everything they say slide and forget about it. Smile with gritted teeth.
I had someone like that when I was pregnant it drove me batty. But you know what your body needs and requires, no one else and every pregnancy is different.
At your stage I was eating pineapple like crazy, I was aware it could bring on labour but bugger it! Do what you want and what you feel comfortable with.
If they want to control a pregnancy so much well they should find a way to be pregnant again or be quiet. =)