Help my sex life

OK so me and my love have been together 7+years, we have 2 beautiful children together and I couldn't ask for a better man!!! For the past year and some months I've been having a problem with enjoying sex!!! How do I tell him that it's boring and not good anymore without hurting him and ruining our relationship? I mean he loves sex all I have to do is walk pass him and he is ready I love that in him because that let's me know he is still attracted to me after all these years!! I don't want to crush his ego and keep turning down sex because that would bring new issues into the relationship someone please tell me how I can fix this!!!