It's a super hard situation when your partner still drinks. Even harder if they're drinking in front of you. If he promised to not drink around you after you left rehab, I would "kindly" remind him of that and explain how difficult it is for you right now and you need his support.
My husband and I quit drinking together, then he caved. He continues to try to abstain...sometimes hiding it behind my back... I think that my husband thought that I might go back to drinking with him after he caved (like I have so many times before). Once he realized how serious I am this time, he's been making more of an effort himself to stop drinking. If he IS still drinking, he's hiding it and he wouldn't drink in front of me.