Help me please. 💔

What do you do when you feel like your boyfriend doesn't love you anymore? We've been together a year and a half and have been living together for he past seven months. He used to be super creative and fun and passionate. Now he just seems like he doesn't care. He sits on his phone the whole night, bugs out if I go anywhere near his phone, and has seemed very distant lately. Is there any advice on how to handle this???