Should I be happy being last on the list?

I have been dating a man for almost 2 years. We are both divorced and have children. He is still supporting his ex wife and for the most part his adult children. He is very responsible and a good father, however, on the weekends when we are supposed to be child-free, one thing or another always compromises our adult time together. We have not had alone time together since mid March. It doesn't seem to bother him at all. When I discuss this with him, he comes up with reasons. I believe, people make time for the things that are important to them. If I am not important enough for him to set boundaries with his ex and his children to allow for couple time, then I suspect I will not ever be. In addition to this our relationship is mostly on weekends which is why the weekend time is so precious.