Quick background, I've been with my s.o. for a bit over a decade and while at first it was very chaotic, massive kudos to him, he has gotten a lot more perspective into the BPD and the emotional swings are more moderate. 

But his main thing, as I understand it, is the feeling that nobody loves him, that he somehow doesn't have enough close friends (he can name 3 myself excluded ... as an introvert this seems normal) and a need for acceptance. He will say things like "I just need for someone to tell me I matter" and "no matter how much I try to change, everybody hates me". 

To me a lot of this makes very little sense or represent expectations about average adult friends that are a bit out of the norm ... in that really most friends will never out of the blue tell you "you matter", even if you do and that the fact that they are your friend and hang out with you kind of demonstrate it and also that you can't change in some magical person to make people -like- you.

But the issue is, I don't know how to approach my s.o. when he is feeling like that. He's obviously in tons of hurt yet I don't know how to support him. I'm afraid if I try to challenge what I see as misconceptions will be taken the wrong way. 

I'm afraid that if I tell him that he matters to me, because he does, it will come off as a sort of cheap consolation prize statement or disingenuous. 

Any tips? What's the best way to approach someone going through a rough emotional pass. He tends to just say I'm tired, not eat and then usually later will put words on what is going on. But then I don't know what to do. Is the self-isolation an attempt to see if I'll insist on talking to him and being close .... like some weird test to see if I love him, or should I just let him be and have his time alone.

Any tips, advice? I know every person and situation is different but I thought I'd ask.

Thank you. 