Bf of 3 years stopped loving me

After 3 years i can sense that my boyfriend is losing feelings. He tells me he loves me which is why he “puts up with” me and that he stays with me because he wants us to last. That makes me feel terrible though because I feel as though our relationship is based off of him not anticipating change since he’s accustomed to me.

I don’t get much affection from him as I used to and when I ask him why he loves me all he says is because I “guide and care for” him. It makes me feel like his mother rather than his girlfriend 😑 what do I do ?