Hoping that this sad person we have spent so much of our time, energy, and love on can at least find some happiness someday even if it's not with us?
someone who suffers from a mental illness will never "find" happiness like a pirate finally comes across the buried treasure he's been searching for.
"happiness" is a state of mind. you cant find it. you create it. period.
because of the state of mind a BPD is in, there is zero chance of creating the reality of happiness in their world. they don't have the knowledge or skill set to create such a nature. the only thing they know how to do is mirror someone else's and take it on as their own.
a person with BPD has no sense of "self". no identity. how are they going to create happiness when they don't even know who they are? what is happiness to a person who relies on mirroring another persons characteristics?
you can't define happiness for yourself if you have no self. impossible.
the only thing a BPD will find, is another host to supply them with the emotional substance they lack to produce themselves. that's all they know. that's how they survive.
if you want to "hope" for someone, go look in the mirror. that's the person you need to spend the most time, energy and love on.