The best bit of advice I can give you is that everybody poops! It’s funny that we can get so embarrassed about something we all actually do. The issues though is that there seems to be this double standards when it comes to things like passing gas and bowl movements. It’s ok for boys to do it openly and loudly but not lady like for a woman?
I once read someone that woman pass more gas then men, but it’s just that we try and hide it. I’m not just suggesting to let one rip, especially in a new relationship, but don’t feel embarrassed when you do. If you need to do a number 2, just do it. You can close a bathroom door can’t you? If noises are made you can always make a bit of a sarcastic comment about it after. Humour is a great way to make awkward situations feel more comfortable.
Sometimes you just need to incorporate fart and poop comments into every day talk like it’s just another behaviour. When the situation is made to be more awkward it can feel that way. If you do feel embarrassed, you can always tell the other person you feel this way. Conversations like this can sometimes bring you closer together. That might sound weird but when we are vulnerable towards someone else and open about fears and phobias, it can bring a level of intimacy into the relationship. So maybe talking about poop in a relationship can be a good thing for your future bonding.