I don't … to him/her
Si je l'avais su, je ne lui aurais jamais dit de telles choses.
If I had known, I would never have said such things to him/her.
Tout l'équipage va mourir si je ne lui parle pas.
The whole crew will die if I don't talk to him.
— Star Trek Into Darkness (2013)
Je ne lui fais pas complètement confiance.
I don’t completely trust him.
I don't blame him.
Je n'aime pas Tom et je ne lui fais pas confiance.
I don't like Tom, and I don't trust him.
Je ne lui pardonnerai jamais, pour Boris.
I will never forgive him, for Boris.
— Quand passent les cigognes (1957)
En ce qui me concerne, je ne lui fais pas du tout confiance.
As far as I'm concerned, I don't trust him/her at all.