Never in the mood

Helpp. Me and my boyfriend have been together for 5 years now and for the last few months I am neverrr in the mood to have sex like what so ever or really even do anything sexual at all. I just haven't had a sex drive. I feel bad because he wants to a lot, but I never do and I worry it's pushing him away and he gets upset because we never do anything anymore. Any advice to help this or similar experiences?