stand up for myself or suck it up....?

I have 3 amazing children from 3 seperate very open adoptions. Our latest was from birthparents who didn't get along, their families even more so. My first 2 open adoptions (ages 2 and 4 now) are all relatively comfortable and smooth (well as much as they can be). My delima is with our latest adoption (about 9 months old)... Abbreviated version:The Birthmom's (I'll call her A) family was the one who was pursueing the open adoption. The Birthdad's (I'll call him B) family was resisting it. While we were just all starting to get to know each other our son was born 3.5 weeks early. B was not comfortable with the plan so he didn't agree to the adoption forcing A to parent. During this time A's mom was contacting me telling me they were trying to make B and his family realize that adoption would be the far more pleasant route for everyone. A few weeks later B changed his mind and we ended up moving forward with the adoption plan and brought our son home when he was 2.5 wks old. Move forward a few weeks and we are home with our son and A & B come for a visit for the weekend (which was a very nice weekend we thought). B contacts after letting us know how much better he feels about everything having seen our family and the environment our son was being raised in. A leaves and doesn't respond to my texts but sends texts refering to "MY SON" (her words) and generally negative in general, she needs to talk to me, etc... I find out she is inquiring about reversing the adoption. She says she wants to come visit again and I let her know we need to be able to have a conversation about everything first, but after that she can come (she didn't know I knew about the reversing of the adoption at this point). She basically never responds or achnoledges me again after this. About a month later I get a very nasty email from her mom telling me how cruel I am being to her daughter, how I conned her into the adoption, how they discussed that my children will never feel my love based on how I could treat her, etc... I respond that I've sent her a picture of the baby everyday since we brought him home along with updates, we welcomed her into our home and how she is still welcome if we can have a civil conversation regarding things (I do have 2 older adopted children I need to shield from all this drama) After this, her whole extended family who had been friendly and open until now completely stopped responding to me or achnoledging us on facebook. I get A's reaction, her grief entails strong feelings of anger, denial, regret, fear, etc... They are also very mad because I think they thought they would have some level of control in B and his families involvement, but I won't let them control my relationship with other people and I won't get in the middle of their fight. We visited (a 5 hour drive each way but my daughters birthfamily lives there also) them around christmas and A had my husband (they love him) come over by himself with the baby. We went again last month and he went again by himself with just our son. I am totally fine with this (more so than my husband) because I don't want to hang out with these people that act like I conned them into the adoption. A's family and friends even all still call him by his birthname, not the name we gave him. So this is about where my delima is... The extended family who was so quick to snub me is starting to warm up to me for whatever reason and I'm not really sure how to react to them. I totally get A and her grief stricken 18 yr old girl reaction. I don't get her adult family members acting the same way. The whole reason we can be so open in all our other 5 birthfamily relationships is that we are all nice to each other and treat each other with respect. These people have treated me with no respect, have been the most insulting people I have ever dealt with and then expected me to listen to their demands out of "gratitude" (A's moms words not mine). I have corresponded with A's extended family more recently and am always polite and accomidating but as things move forward I am not sure how to deal with this family.... Suck it up (which I'm inclinded to do and hope this isn't a pattern) or or stick up for myself and not tolerate the disrespect if our relationships move forward (which I would do with anyone else). I'd love some insight from anyone on this since I struggle with what I think I should do and what I want to do...