When a pwBPD can't find a replacement

[LuckyTown]

Could someone with more knowledge than me about BPD help me out with two questions... .

1) What is life like for a person with BPD if they cannot - for one reason or another - find a replacement for the former romantic partner they've painted black?
For example in a case where they are too distrustful to reach out to new people and all the people they have around on a daily basis are unwilling to get close to them.

2) Can a relative serve as a replacement for a romantic partner?

I know people with BPD are individuals and don't always act the same but I'm just asking in general.

Thanks in advance for your replies.

[Curiously1]

For mine, I know she'll just keep hunting for somebody new. I know for sure that my ex cannot be alone and cannot stand it.
She told me she gets super depressed if she does not have anyone around and just cannot function normally. She feels very empty inside as she described it and just afraid of being alone. She needs a distraction away from herself cos she really does hates herself... .deep down.

My ex is career driven and a workoholic and so will be focused on that aspect of her life. She also uses social media to vent her opinions and emotions daily and people/fans reply so that may help her self-soothe temporarily. From last I know she still kept being friends with my replacement who is friendzoned again but she may still be using casually? Who knows! So yes, I think others such as friends can be a kind of replacement whether used sexually or just for their emotional support, time and company... until she finds somebody she really fancies again. Anybody who can fulfil her needs really. No idea if she's found someone new. Don't know if she is still friends with that friend either. I don't check up on her anymore.