How often would you like to hear your partner tell you they love you so that it doesn’t lose its novelty but you never doubt it or forget it?

Never. It's such a vague expression and its underlying promises are different and means different things to each person and can result in misleading expectations which can lead to so much disappointment.

I would rather they show me by actions
At least then I will know for sure how much they love me and in which ways exactly.