In many ways it sounds like your JW parents are heads and shoulders above many in the Tower. Be as positive and loving as you can with them, while understanding the pressure the Tower puts on them to treat you like dirt. Hopefully in the end true love will continue to bring you together.
Just thinking out loud.....
Your Mum unquestionably does love you and your husband. Your close relationship with her was real and will be real again. However, she is thoroughly confused by this strange turn of events. Try to imagine how you would have felt only eighteen months ago, if your mother had suddenly (remember: it seems quite sudden to HER) announced to you that she was renouncing Christianity (which is what SHE thinks you've done) and become a Hindu (just an example). Your mother is a decent person, she does still listen, all is NOT lost. Plant seeds, don't transplant trees. (Too much, too soon.) She'll come around. (And when she does, your father will come along with her: he's always been the sort to go along to get along.)
Besides, you could always hold the (future) grandchild(ren) hostage. . (I'm not really advocating this.)
When the "Sisters" spread too much gossip/slander about you, your Mum will be faced with a decision to "fish or cut bait". When she sees the "lovin' brotherhood-spiritual-paradise" for what it is, she'll choose YOU.
bennyk- "Plant seeds, don't transplant trees"...I love it! I'll add that to my list of life mottos. Maybe you could have that as the font-page main article title in the January AKM (Apostate Kingdom Ministry). I mean...shhhhh! there's no such thing as the AKM. ;)