Pretend Relationship?

My fiance and I have been engaged for 4 months. We both agreed to wait until his baby from his ex was born before getting married but he wouldnt set a date. Now the baby is here and he has told me i have to take off my ring when we are around his ex or it would hurt her feelings. It hurt my feelings to take it off but I got over it and did it anyways. Then it escalated into me not being allowed to sit by him, which for some reason I obliged. And now I cant even say anything that might imply we are in a relationship if she is within hearing range. We fought this morning about that and he told me that I didnt have a real reason to be upset about it. I dont have any friends where I am so the only time we get to be actually together is when we are alone, but nowadays all he does during that time is sleep.

So i guess what i want to know is, is this all fair to me? I feel like he should stand up for me and let her know how it is instead of walking on eggshells to please her.