This totally sucks. I'm sorry.

Let's focus on the big picture of this problem. As much as she is trying to push you away and cause fights, at the end of the day it doesn't matter. I'm absolutely certain that it hurts, and you are trying your best... but it just doesn't matter. What DOES matter is that you and your new hubby show a United Front. If you aren't included in the pic, he shouldn't participate either. He needs to stand up to this woman and shut down her behavior... not give in. And not just the photo - you two are a team now. If this marriage is going to work, he needs to put you first, no matter what. He needs to step up and handle this. I highly suggest marriage counseling...IMO, every newly married couple should really go through it at the first sign of trouble...the sooner you go, the better off you will be. Don't think of it as "We're failing", but more that you really want this to work and this is going to help you understand each other's needs.

At the end of the day you two are the most important. After all, it's Your life and Your relationship. A COUPLE is only 2!