If you go, you're not gonna care about anything. Not this ship, not Soran, not me....

Guinan:

Soran is a name I haven't heard for a long time. Picard:
You remember him? Guinan:
Yes. Picard:
Guinan, it is very important that you tell me everything that you know. We think that Soran has developed a weapon, a terrible weapon, one that might even give him enough power to destroy an entire... Guinan:
Soran doesn't care about weapons or power. He just cares about getting back to the Nexus. Picard:
What's the Nexus? Guinan:
The energy ribbon that destroyed that ship was not just some random phenomena traveling through the universe. It's a doorway to another place that we call the Nexus, and it's a place I've tried very, very hard to forget. Picard:
What happened to you? Guinan:
It was like being inside joy. As if joy was something tangible and you could wrap yourself up in it like a blanket, and never in my entire life have I ever been as content. Picard:
And then you were beamed away from there. Guinan:
Pulled. Ripped away. None of us wanted to go, and I would have done anything, *anything*, to get back there. And once I realized that wasn't possible, I learned to live with that. Picard:
What about Soran? Guinan:
If he's still obsessed, he could be a very, very dangerous man. Picard:
Why would he destroy a star? Thank you, Guinan. Guinan:
[he stands and moves to leave]
If you go, you're not gonna care about anything. Not this ship, not Soran, not me. Nothing. All you'll want is to stay in the Nexus, and you're not gonna want to come back