Caught in the Middle

My daughter gets married in two weeks. She recently told me she does not want my husband (second marriage) at her wedding. They have had a strained relationship and don’t spend time together since some hurtful history between them several years ago. I understand her request and think it would eliminate anxiety if he didn’t attend but he wants to although I am not sure why. I want/need to decide if it’s best to support her wishes or encourage her to let him attend. He has suggested this could mean the end of our relationship if he doesn’t attend. I have learned in Scholars to love my husband as he is. I cannot expect or force my daughter to do that as well. This is looming over me rather than looking forward to the event. I want to make a decision about how best to proceed.