I have a sil who is identical in age to me, went to same university at same time and has similar interests to me. However she is completely uninterested in me often to the point of being rude. Her children are now beginning to copy her and extend that same "friendliness".. not.. to my kids. Can take it for myself but cannot bear to see my kids treated badly. Only problem is her husband who is very nice is dh's only family member. Any tips?