Partner with pwBPD - engulfment?

I'm seeking some advice around the topic "fear of engulfment". I understand "fear of abandonment" and ways in which you can respond etc. And I understand that engulfment is the fear of losing oneself because a pwBPD doesn't really have an identity and in relationship yours becomes their etc.

My partner is struggling with this. He's been trying to just push it under the rug so we don't argue. Instead, he's just endlessly saying how bored he is, wanting to take drugs again and snappy.

We had a disagreement last night, where he started with blaming me for the reason he doesn't have friends. In truth, the one friend he does have I dislike (he brings weed to his house and doesn't care that weed impacts his mental health and could get fired and this friend is arrogant, and has behaved incredibly inappropriate towards my partner in the past), in terms of other friendship, he has made pretty awful friends because they've all been focused around drugs. But he believes that it's the relationships fault - in part he is right, without me he'd be using, and therefore around those friends.
What do you think about this?

It's better to be without friends than with such guys.

It is always worth staying away from such bad groups of people. They certainly have a negative impact on a person. You should seriously talk to him about this if you want to help him. When a person has no friends, he will be ready to join any circle of people just to be a part of something more than just loneliness. You should explain that it should be stronger than this. I have nothing against medical marijuana, since I buy cheap weed Canada myself to get rid of insomnia. You should also explain to him that it is not necessary to use marijuana so often, since in the long run it has a great impact on the brain.