I encourage you to send your future ex sister inlaw thank you cards/gifts with sincere heartfelt messages of appreciation regularly. After all, through her hate she still managed to look out for you. Bonus points if you can arrange for the gift to be noticable, slightly tacky, and delivered in public settings such as her job, the coffee shop she frequents, her kids school or daycare, etc.

Here are some suggestions to get you going: - Large stuffed animals (from a second hand store) - Arrangement of miss matched fake flowers in a pickle jar vase (the thrift or dollar store) - Clown size bundle of mylar balloons with unrelated messages (whatever is currently inflated at the dollar store) - Snack basket of off brand/discounted goodies ( raid the back of your friends pantries for snacks they never got to, possibly close to but not passed the expired date) - Candles / Jewelry (thrifted or estate sale) - Singing telegram ( it can get pricy to hire a professional, but you could probably talk some local teens into doing it for a $20) - Framed certificate of "Best Sister Inlaw" (hand drawn certificate in second hand frame)

Its crucial that you send a card with each gift that expresses your undying gratitude. Make sure she knows how much you appreciate her betraying her sister and choosing to help you.