Horrible matron of honor

My sister is getting married in Nov and I am her Matron of Honor. Only problem is my husband and I will be moving out of state soon so I will have to fly from the new state we will be moving to, back to my hometown for her wedding. No big deal. Well her bachelorette party is what is kind of stressing me out. She wants to go to the keys for 4 nights and the airbnb she is wanting will cost each person $400 for 4 nights. And that’s divided into 8. Plus the flight, plus food and alcohol. She estimates each person will spend $1000 but I can see that it will go over $1000 real quick. Now my husband will stay home and work while I’m gone. So we have to find child care while I’m gone. So more money spent unless I fly with him and drop him to my in laws. Another thing, my husband and I haven’t even gone on our honeymoon yet and we’ve been married almost 2 years. Spending this kind of money on her trip will delay us a family vacation even further. Or a honeymoon. I know I can afford it, but we won’t take a family vacation for another year or so if I do this and I would hate to do that to my husband. Idk what to do. I don’t want to tell her no, because her friends all said they could make it but yet I’m her sister. I feel the need to be there. But I don’t want my own family to suffer if I go.