Natash, awesome plan. Go crazy planning the party without your W, make it the best your D5 has ever had, god only knows the kids deserve every additional dose of happiness. Think of things she will enjoy with her friends, what she is really into these days make that the theme of the party. Ask your D7 for help, this can be a daddy-daughter project and she can give you some great insight into what D5 might enjoy. Make it a day you all cherish forever, oh and yes sorry your W was not invited, you were too busy to remember or miss her