Michael J. Fox Opens Up About His Health, Life with Tracy Pollan: 'I'm in a Really Good Groove'

Three years ago, Michael J. Fox had an accident that greatly tested his optimistic outlook on life. In recovery from spinal surgery, the actor, who has been living with Parkinson's disease since 1992, had a nasty fall and broke his arm.

"I felt so sorry for myself in that moment, lying on the floor, a bag of bones," recalls Fox, 60, in this week's issue of PEOPLE. "And I thought, 'Who am I to tell people to cheer up? Because this sucks.'"

But ultimately, "I realized I could find gratitude," says Fox. "You can be a realist and an optimist at the same time. If I don't accept it, I can't move forward."

Now, Fox is moving forward — and looking ahead. On Saturday, he will celebrate 20 years of his Michael J. Fox Foundation with a star-studded benefit, featuring performances by Sting and Brad Paisley.

With the Foundation, which has raised over $1 billion to date for Parkinson's research, "we are loading up all the cannons we can and pointing them at the target," Fox says. "One of them will fire and it will happen. The disease is a problem that will be there until you solve it. But we're hopeful."

Physically these days, "I'm in a really good groove," says Fox. "Every day is different. The circle [of what I can do] gets smaller. But I'm happy I've found things in the middle of the circle that can't be touched, like my family and the time I have with them."

And with their youngest daughter Esmé, 19, off to college, Fox and his wife Tracy Pollan, who are also parents to Sam, 32 and Aquinnah and Schuyler, 26, have found themselves empty nesters.

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"We did an interesting thing," says Fox. "We sold our house and we went to Santa Barbara for a couple of months. We're going to go to Malibu later this year and hang out. We don't have anybody to pick up at school!"

Still, the family remains closer than ever, says Fox, no matter how far apart they may be.

"I have a great family," he says. "My kids are spectacular and they apply their energy to change and making things better. You should see our family text chain. It goes on forever!"