DH and I have been married for about 5 years. Since before we were even married, DH seemed strangely close to his brother's wife. At first I thought nothing of this, until I met her. SIL is the ultimate "mean girl." She is in love with herself, brags about everything, especially things she knows she has that I may not, constantly looking for flattery from both her husband and mine, and since the day I met her pretends I am not in the room. She won't speak to me or eye contact but only talks to the men, like she is holding court with how adorable she is. She is very spoiled. She grew up with money and refused to work a day in her life, even before kids. She is an expert at making little comments and jabs at me that the men are completely oblivious to and then sitting with a satisfied smile while I silently stew. They are literally completely oblivious of everything about her.
DH did nothing but sing her praises from before I even met her, and I kept my opinions about her to myself for the first couple years of our marriage, even when visit after visit, she exhibited this nasty behavior. Less than a week after I found out I was pregnant (and having some early complications), DH jumped on a plane to go support SIL when her father died. Since the day I have met him, he calls her family "his family" and it took years before I got him to understand that her family are his brother's in-laws, and even then he was only able to consider this as a possibility when I asked, "Well, does your brother consider my parents to be HIS family?" His brother expects my husband to drop everything when his wife has some new drama good or bad, but I/we have had our own problems (health scares, pet deaths, etc) over the years and we have never looked to the brother for any sort of sympathy or support, nor would he be bothered to offer it. When we had our first child, DH did not get me flowers but a year later, when his brother's wife had their first baby, he sent her flowers to the hospital. I was furious and at this point, I let my feelings be known. It all came out and caused a huge argument. DH absolutely doesn't see my side of this, thinks so highly of his brother's wife, scoffed when I gave examples of nasty things SIL has said, and refused to even consider the validity of my feelings until I finally said that I refused to spend any more time with this woman. That he can see them on his own.
Now his entire family hates me, because of course, SIL was the original wife and I am the one who shunned their little darling. Her husband adores her and clearly, mine does too! She can do NO wrong in their eyes. DH and I have had a strained marriage in general, and it's so upsetting to me that she is Miss Perfect in his eyes while I am the person he argues with. A large part of the source of our arguments is that he has accused me of having such a problem with his family, when I am simply responding to the way I have been treated by them! I have expressed countless times how excited I was to finally get a sister/SIL, only to feel like I was shunned from day one, but DH views it as me vs his family and by his family, he means his brother's wife, too. I just feel like they made me the outcast and my DH has not helped matters.