Family Members Don`t Get Along

My take on your situation would be to accept and honor your mother`s feelings. From the sounds of it you and her side of the family are not close at all and there seems to be quite a bit of tension. It would be better not to invite them if there is any chance of unneccesary tension or unhappiness. It may help to think about it in a different light, have they invited you and your family to special events and occassions? Graduations? Weddings? Anniversary Parties? From the sounds of it, probably not. And if you mother is so adiment about them not being invited and hasn`t spoken with them in 10+ years there is probably something serious that drove such a drift between them.