Hi and welcome @Sirihawi
Yes, the lack of motivation is surely a 'thing' and not just with BP either. I'm really sorry you're experiencing such apathy.
I talked with my psych and GP about this very topic a couple of years ago. I was admitted into a psych ward for planning my demise. There was no passion, emotion, drive or will in me anymore.
Like any machine, our bodies and especially brain/nervous system, will show signs of wear and tear if it's pushed to its limits too often and over long periods.
For me, living alone, still dwelling on past trauma and dealing with too many problems after a major breakdown, all bought me undone. My brain closed down the emotional part and only allowed enough function to get through my day. I was left with a feeling of separation from others and matter-of-fact attitude to my presence in the world.
Planning as I did seemed rational and necessary. I look back now and shake my head. On the ward I wasn't even allowed to dust my side table or sweep the floor. It was a bizarre feeling which led me to fall apart. After all, I could. At home I couldn't.
And I think that's what happens sometimes. We just don't feel we have the space to fall apart or be ourselves without day to day life getting in the way. Our brains are tired and sick from traumatic situations and the pressure we place on ourselves, so it makes sense it eventually limits what we can achieve. The first thing to go is our passion.
Even though our brains are sick, it still realizes we need rest. That's why we become disinterested; it stops us from becoming too busy and creating more things to worry about or focus on. In essence, we're forced to slow down.
It's not your fault; that's the main point I'm making. It's just how the primal brain works to help us survive.
I hope this makes some sense Siri...
My best;
Hope 