How do you say are the only one im missing in french?

There are a few ways to say "you are the only one I'm missing" in French, depending on the nuance you want to convey:

Formal:

* Tu es la seule personne qui me manque. (You are the only person who I miss)

* Tu es la seule que je manque. (You are the only one I miss)

Informal:

* T'es la seule qui me manque. (You are the only one I miss)

* Tu me manques plus que tout. (I miss you more than anything)

More poetic:

* Tu es le seul vide que je ressens. (You are the only void I feel)

* Tu es l'absence qui me hante. (You are the absence that haunts me)

Important Note: "Tu" is the informal "you" used with friends or family. "Vous" is the formal "you" used when speaking to someone you don't know well or when showing respect.

The best translation for your specific context will depend on your relationship with the person you are talking to and the emotion you want to express.