This was a good Mother's Day. DS came back to the house. He wished me a happy day right away and he had a gift for me that he obviously did on his own. He also spent a little time with XHs girlfriend who has been in his life for a decade. She lives separately from XH but she's been another mother to DS and I'm proud of him for recognizing her, too. 
And not surprisingly I heard zero from the skids. It was OSSs bday earlier in the week and I texted him happy bday and he didn't respond to that either (DH thinks they are super conscientious and polite). And I'm closer to being a mother figure than XHs GF with DS--- I'm married to their dad and have been in their lives for nearly a decade. Pretty sure DH didn't prompt them to say anything because he handed me his phone to do a little tech support with MIL and in sending her texts I could see that all he had done lately was tell BM happy moms day. I don't care. I find the difference interesting. Frankly if they had done anything I would probably have fainted from surprise.