Welcome to SR, Schab. There are many mothers of addicts here working strong recovery programs for their codependency and they will offer you solid advice.
I am not a parent of an addict but I know enough about addicts to know that whether you are a thousand miles away or one mile away, you will not be able to talk him into, nor bribe him into, nor guilt nor plead nor threaten him into, recovery.
Keeping good boundaries and not enabling him helps him, because as long as life is working for him--food and shelter and drug money--then he will keep using. It is when using becomes a nightmare that an addict seeks help, and the nightmare can't happen if everyone is keeping the addict comfortable.
So stay where you are. All the experts say that our prescription is to take care of ourselves. To "find serenity and even happiness, whether the alcoholic [addict] is still drinking or not." That is a quote from Al-Anon, a recovery program for friends and family members of alcoholics and addicts. Nar-Anon is for friends and family of drug addicts. You can google those, with your state, and you'll find some meetings. There are great free pamphlets, at the meetings, on dealing with addiction in the family. And you can just sit and listen to people share their experience and recovery from the effects of addiction in their lives and within their families.
We are glad you found SR. And you even have the right font now.
On the opening page of the forum you will see links labeled "Sticky." It's a good place to start your recovery.
Your son is not a hopeless case. People recover from drug abuse. We have several members who are recovering addicts.
And the chances for an addict to recover are much better if his family first finds recovery. Even though he has enablers within the family, your own recovery will make a tremendous difference. You will speak to him and to other family members from a place of genuine conviction and solid education about the right and the wrong way to deal with an addict in the family. You will feel less guilt and stronger resolve. You will have faith in your choices. You will be able to say that word addicts hate most--NO--and not hate yourself for it. You will be proud, instead. And hopeful.
We will support you as life unfolds and change happens. Keep taking care of you. You have had a major loss, the death of your partner--I am sorry for your loss-- and you are re-building your life. You are on the right path.