My husband and I say this, it reminds us that we are first in each others lives. It may not be accurate for you, but I wanted to share.
"You are all I need, but not all I want"
My husband often struggles with ths, the other man I love is my best friend and we have been "together" as friends for over 12 years now, with actual sexual relationships interspersed. Way longer than my husband and I have even known each other, much less been in love. My love for my best friend is very strong, and there are times when I know my husband doesnt feel as loved as he knows I love my best friend. That little saying helps him, and it reminds him that HE is the one I married.