Lopez, 52, is promoting her latest film, Marry Me, and is clearly more guarded in what she says about her relationship.
"I won't talk about it a lot," she says in the interview which took place in late December, of her and 49-year-old Affleck getting back together. "We've both grown. We're the same, and we're different. And that's what's nice."
"Yeah … having a second chance at real love … yeah," she continues. "Like I said, we learned a lot. We know what's real, what's not real. So it's just — the game has changed."
She doesn't see another breakup with Affleck in the future.
"I don't think we would have got back together if we thought that was where it was headed," she says. "We feel like what we found again is so much more important, and how we protect that and how we live our lives — what to share, what not to share — is the balance that we have now, the benefit of experience and the wisdom that we gained over the years."
In the candid interview, Lopez opens up about constantly feeling like an "underdog" in the business since she didn't grow up wealthy or with industry connections. She recalls how she was treated badly when she and Affleck first got together, and her producing partner, Elaine Goldsmith-Thomas, notes that Lopez was never given credit for her own success, which at the time included a No. 1 album and box office hits.
"It was brutal," Lopez acknowledges. "It's one of those things that you bury very deeply so you can move on and get about your business."
"It's funny because Ben and I were together, and we were so in love," she recalls of that time. "It was one of the happiest times of my life. But also, there was this other thing happening where we were being criticized, and it really destroyed our relationship from the inside out, because we were just too young to understand at that time what were really the most important things in life."
Lopez has since gone to therapy and says she's also become "much more spiritual" since having children -- 13-year-old twins Emme and Max, whom she shares with her ex-husband, Marc Anthony. She reflects on her past failed romantic relationships, which have been heavily scrutinized.
"When I was in my forties, it was like, 'Well, you're not really loving yourself. You're allowing things to happen in your life where you're overachieving in your work, and your personal life … is not…,'" she acknowledges. "And it fueled my artistic life, which is great in a lot of ways, because it made me want to overachieve. It made me want to feel better. It made me want to do better and be successful and be better as an artist and grow, and I have. But also, you just want to feel good in your life."
"It's not really even your first love that teaches you what love is," she adds. "It's your mother and your father, what you were taught as a child that life is and love is, through how your parents are with you. Those are the things that you have to go back and work on and examine, when you are having relationships and repeating patterns and going, 'Oh, what is this happening for?'"
Meanwhile, career-wise, Lopez still feels she doesn't get all the respect she deserves.
"It's just 20, 25 years of people going, 'Well, she's not that great. She's pretty and she makes cute music, but it's not really this and that,'" she notes. "You know, I think I've done some nice work over the years, some really nice work. But there is a club that I just wasn't a part of. And I always acted like, 'Yeah, I'm good. I'm fine. I'm OK.' But it hurts to not be included. I don't know if I will ever be. There is an inner circle, like, 'We are the great artists.' And then there's the pop artists."
Still, Lopez says she's thankful for everything she's achieved and always makes sure to remind herself daily that she is enough.
"I try to always live from a place of gratitude," she says. "But today, especially, if you ask me what my first thought was, it was, 'Thank you. Thank you, God, for this day. Thank you for my life, what it is.'"
In her latest film, Marry Me, Lopez plays superstar Kat Valdez, who is publicly humiliated when she finds out that her fiancé (played by Maluma) is cheating on her right before they're set to get married. Lopez says she can definitely relate to the character.
"I had to keep reminding myself: You know what it’s like to be onstage in front of an arena full of people and something embarrassing happens. That's happened to you," she shares. "What do you do? What does it feel like when it all falls apart and you go home and you're on the TV and they're making fun of you as if it's not painful? How does that feel? You know what? You've cried in a puddle on the floor too. That's what it feels like. Or going underwater at that point where you feel like you're drowning, suffocating in your own decisions that you know are not the right ones."
"You start realizing there are no rules," she adds about continuing to stay true to herself over the years. "There's only what you feel is right for you. Because that's the person you've got to live with at the end of the day. Any time I've gone against my gut and my instinct, I've ended in misery."
Last month, a source told ET that Lopez and Affleck are "madly in love" and that an engagement is coming. Watch the video below for more.