How would you go about it

My best friend had her bday few days ago and today is the bday dinner, the reservations are for 7:30 but on top of that today is my husbands best friends bday, whom I’m also friends with and his gf. My husbands friends dinner is at 7:00 and so my idea was to go to my husbands friends bday and then be at my friends dinner, latest 7:50. Now, my best friend and our other friend are saying how they are upset with me. How me doing both dinners like that is pointless and why do I even need to show up for my husband friends dinner, they are not happy with me coming late to their dinner. Anyways, these are the friends that not once showed up on time for any events I had. At times they be over an hour late. Like, I’m not even sure that they will make it to this dinner by 7:30.