Making plans with the SO

My SO rarely suggests to go do something fun with me nowadays, but every time he does, the plan either ends up not happening, or he invites all of his friends along such that he and I will have zero alone time (more often than not, it's an activity that he and his buddies will have fun with, while I'm watching on the sidelines). We haven't had an intimate him-and-me-only date in almost a year. If his friends invite him for a plan or spontaneous adventure, he is always eager to come along. Am I just becoming less of a priority to him? Do I not matter as much anymore? How often do you and your SO foster time to do fun activities for yourselves??