Wedding drama

Not sure if this is really the place to post this but I do have to talk to someone about this. My mother I have a tradition where every year we go to a corn maze. This year will be my sons first corn maze. We have it planned for the 26th. My dad who I have had a very estranged relationship with even before he cheated on my mom with his now current girlfriend is now getting married on the 26th. He told me today the 9th. He has been trying very hard to reach out ever since I had my son, and I do frequently hang out with him and his girlfriend. And I feel extremely guilty not going to the wedding. At the same time I don’t feel should have to cancel my plans because he wants to get remarried last minute. What would y’all do? Go to the wedding or go to the corn maze.