OP, I have learned to invite people to come with me to mass or to some less formal event at my parish in a casual way. I think that if we make a big deal of it, some people feel pressured.
I used to be more hesitant about inviting people to mass with me. I have an aunt who went to Catholic school as a child. I’m currently the only practicing Catholic in my extended family. I just left our family reunion one Saturday afternoon and went to mass and returned. When my aunt came back and found out where I had been, she said that she wished that I had told her because she would have gone to mass with me. (She married a Protestant who does not go to church and fell away from church herself in the '60’s.) I could have fallen over from surprise! I might have missed an opening for her to come back home!!
For someone who is having a hard time, maybe you could say, “Hey, I’m going to mass at 5pm on Saturday. Would you like to go with me and then out to dinner?” Maybe inviting the person to go to a Christian concert or to a church carnival or to a women’s fellowship where it is mainly socializing? My parish has an annual Advent brunch which non-Catholics and fallen away Catholics can enjoy because it an excuse to dress up and be served brunch by nice men in a festive atmosphere. We have fish frys during Lent which can be a fun reminder of childhood for people who grew up participating in Catholic life. I also know some Catholics who have “come home” after going on a retreat with a friend.
I hope you find something that will lift this person up in their struggle for sobriety.