I am 52 yrs old and I have seen many adult kids who do this to the boy friend girl friend of their mom or dad. Your boy friend has only been in her life for 4 yrs and maybe has some guilt but that is still no reason for him to let her disrespect you.
He is sneaking behind your back and smoking weed and if he is not drinking hewill be drinking soon. When you are a recovering addict or alcoholic you have to be sober and clean from everything.
I hate to say this because I know the older you get the harder it is to find love. This man lies to you sneaks around while you are at work and allows his daughter to call you every name in the book. His refusing to seek counseling says something about how much he cares about your feelings./ I have a feeling if he went to counseling he would lie there too. I have been friends with and had family who were alcoholics/addicts and they are the best liars in the world. They can look you in the eye and say how great they are doing and how they are so thankful you helped them and they love this new life, and a minute later be out the drinking smoking weed or doing whatever drug it is they do.
I think as hard as it is going to be that you need to let him go. Let him go back to living in the basement or go live with his daughter. He has been lying to you all along and I think it is a slap in the face to let his daughter talk to you that way. It will be only a matter of time before he messes up his job due to smoking/drinking. Then you will be paying all the rent, all the bills and who do you think will be paying for the weed that brat of a daughter smokes. Not only that but if he is smoking weed, that means he is buying it and if he is buying it that means he has had it in your home. Sure many people say weed is not that big of a deal but one joint/blunt can cost some people their job. I am sure he will swear up and down he never buys it she does .
I do not want to sound hard or mean but he has shown with his actions how little he respects you or respects what you two have decided. I will say I think a month is a bit to long to go without talking to a son/ daughter, but its way beyond that now. He should have told you I think that is too long of a time and the two of you should have talked it out. By him going behind your back and hanging with her and smoking with her every day is the reason that she talks to you that way. he should have stopped it the very first time she said it or disrespected you. It is to late now. The damage has been done, she knows she has full control can say whatever she wants and he is going to side with her.
I would ship him back to the basement or to his daughters you have done so much for him and in return he lets some 20 something girl come along bad mouth you, disrespect you and has had him lying to you for how long???? Let him go , maybe after liviing with his daughter for a couple of months he will realize what a wonderful woman he lost and come back crawling. I am telling you from experience with alcoholics/addicts if he is smoking heis drinking ans if is not drinking he will be very soon. Alcoholics and addicts are the best liars in the world.