Abigail Spencer Talks About Her Friend Meghan Markle 

Star Abigail Spencer on Her \'Lovely Friend\' Meghan Markle

While Abigail Spencer has worked with plenty of talented people, good friend and former

costar Meghan Markle has always stood out.

“Meghan Markle is one of the loveliest human beings on the planet, in the world,” Spencer, who stars in NBC’s

, tells PEOPLE in this week’s issue. “I’m just so excited that the world will get to experience her loveliness, and I really think that with her platform for charity and her fortitude — she’s going to have a great moment to change the world. If anyone can do it, it can be her.”

Prince Harry and Meghan, who announced their engagement in November, are inviting more than 2,500 people to the grounds of Windsor Castle for an up-close view of their May 19 wedding day.

Meghan Markle, Abigail Spencer and Bonnie Zane

Spencer adds, “I’ve known her for so long. I’m just excited the world gets to meet the person I love so much. It’s just so wonderful to see her so happy and so in love.”

are behind her, Spencer credits each role – big or small – to where she is now.

“I had been working under the radar for 10 years, and this was the first time anybody had seen me act really except my mom and my friends and my agent,” she says of her days on

. “I had to be like, ‘Am I a good actor? Yes, keep doing it. Don’t quit.’ ”

Now, Spencer is returning as time-traveling college professor Lucy for the second season of NBC’s

“When I was a little girl, I always wanted to be an actor,” she says. “The fact that every day, I roll onto the Paramount lot – like full sweatpants, full acne, full whatever state I’m in, and the two security guys that work at the gate, every morning, ‘Hey Abigail! How are you? Welcome back to Paramount.’ They wave and they smile and they love the show and I get to pull in. I’m living my dream.”

But her best role yet? Being a mom to 9-year-old, Roman.

“Right before I became a mother, I had this really deep longing for my life to not be about me, and I didn’t know how to get it,” she says. “The second that I found out I was pregnant, it was instantaneous—my life was just no longer about me.”

“Every day is a new challenge,”she adds. “It does require a big support system, so there’s a lot of delegating. Becoming Roman’s mom was such an incredible reinvention of myself. I started writing. I wrote a pilot that I sold. I started writing films. I just felt this creative rebirth on every level when I became his mother.”

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