Boyfriend doesn't want to have sex....

I've been with my bf for over 3 years now. We've usually done it 3-5 times a week, with occasional "dry spells". This means that maybe for a week we won't do it....I think maybe ONCE we went a week & a day without doing it, but once we come out of the "dry spell" we do it a lot until the "dry spell" comes again.

It's not been 6 days since we haven't done it, & according to my bf he hasn't been in the mood at all. Every day he reassures me & tells me he still loves me & that it's going to come soon, & when it does it'll be a lot.

Today he told me he's a little worried as to why he hasn't been in the mood as he thought he would be since we haven't done it for 6 days as of today...but I'm just scared. I know we've done this before & we came out of it just fine, but I'm just so worried it's making me so sad. Is this whole thing normal???