Welcome to SR, you're among friends here who have been where you are.
Sadly, nothing you do or don't do will change whether he gets and/or remains sober. If love could save our addicted loved ones, not one of us would be here.
Maybe take this time to do some thinking of what you want from a relationship and whether you want to be the one doing all the work.
A healthy relationship isn't about two people trying to change each other, it's not about one needy person being taken care of by the other...it's about two people who share common interests and who find joy together just as they are.
Take a read around and make yourself comfortable. My son is the addict in my life, others will be along who have been through relationships such as yours and perhaps they can share how it worked for them.
Again, welcome, I'm glad you joined us.
Hugs