Someone please listen to me

My boyfriend and I have been together for almost five years. I love him with all my heart but recently things have been distant. During the whole month of January I was quarantined so we couldn’t see each other and all we did while I was in lock down was text and the occasional phone calls (that didn’t last very long). And that’s how things have been ever since. Even when we hang out now he barely is able to carry a conversation. Every time I ask him what’s wrong he’s always depressed about something. I don’t think he’s lying about being depressed I do think he’s lying about the reason. I just don’t know what’s wrong and I don’t know what to say or what to do