L'amour fait mal.
Here's a breakdown of the phrase:
* L'amour: Love (definite article "l'" is used because "love" is considered a known concept)
* fait: does (verb "faire" in the present tense, 3rd person singular)
* mal: hurt (noun meaning "pain," "suffering")
Other possible translations:
* L'amour est douloureux. (Love is painful)
* L'amour peut être cruel. (Love can be cruel)
* L'amour blessé fait mal. (Injured love hurts)
The best translation will depend on the context and the specific nuance you want to convey.