Boyfriend vs friends

I've been with my current boyfriend for about a year and a half now. Whenever I try to hangout with my friends, he instantly gets all sad about me not spending time with him, even though we literally see each other every day. My time with my friends is just as important to me as my time spent with him. I just hate feeling guilty leaving him at home alone. He doesn't have any friends himself because he was homeschooled. Any advice?