The Denver native's fiancee, Lauren Bushnell, also encouraged Grimaldi to continue talking through their relationship.
From one Bachelor to another, Ben Higgins has a bit of advice for Nick Viall!
ET's Lauren Zima caught up with Higgins and his fiancee, Lauren Bushnell, in Los Angeles on Wednesday. The two have been busy helping pals Emily and Haley Ferguson film the new season of Freeform's The Twins: Happily Ever After?, premiering March 20. The couple weighed in on Viall's relationship with Vanessa Grimaldi, who he proposed to on Monday night's The Bachelor finale.
"[He's] no longer the Bachelor and that's a really exciting thing," Higgins said. "It sounds like their relationship is off to maybe a difficult start ... He needs to start investing in their relationship more than anything else. That would be my advice. It is a tough season of life."
"I'm sure Nick knows what he's doing now," he added. "He's no longer the Bachelor, and it's time for him just to humble himself and be a good partner."
As for Grimaldi, who spoke openly about fights with Viall several times during the show's After the Final Rose special, Bushnell said the 29-year-old Canadian should continue to talk about her relationship struggles.
"I would just say, 'Talk to people. If you are struggling, talk to Nick, talk to friends, talk to your family -- don't bottle it all up. Also, show some grace, which I wasn't always the best at,'" Bushnell admitted. "As hard as it is to think Ben never intentionally hurt or did anything, it's just the process, it's not necessarily the person. So forgive [and] move forward, which I'm sure they will do."
According to the couple, though Grimaldi and Viall's ability to share the struggles they've had during their debut as a new couple might have been a little awkward, it showed their authenticity.
"I think one thing the After the Final Rose did show us is their relationship is very real, they weren't trying to hide anything," Higgins offered. "So, I think they're authentic. Lauren and I have been there, and we know that time in life is really hard. We can look back and say it is. So, I think they were just being very honest."
"I kind of appreciated it because I feel as though we hear a lot from the lead -- the Bachelor, the Bachelorette -- you're following their journey, you always know how they're feeling," Bushnell noted. "I thought it was nice to hear how [Grimaldi] is doing. I know I can relate. Ben and I have had our ups and our downs."
"I think they're both really good people and wish them both the best," she continued. "It's definitely a journey and I think most couples that come out of The Bachelor can relate on some level."
As for the new Bachelorette, Rachel Lindsay, Higgins and Bushnell say they're already "big fans!"
"Rachel has just absolutely crushed it so far," Higgins said.
"I don't think there's a better person, race aside," Bushnell shared. "She was the person regardless, but it's just so cool and special that she gets to carry that important title [of being the first black lead in Bachelor history.] I love her. I think she's so real and honest and funny and smart and classy! I could go on and on."
While Lindsay starts her journey to find love, Bushnell and Higgins are still without a wedding date -- but said they're "in a good place" to start wedding planning.
WATCH: Lauren Bushnell Says Her Relationship With Ben Higgins 'Ain't Perfect' Amid Breakup Rumors
"We have no wedding updates!" Bushnell confessed. "But things are going well. I feel like we're in a really good place. We're having fun."
"A lot of people have been asking, 'Has life slowed down?' It hasn't really slowed down [but] we both feel a lot less stressed! I feel like we're living life, enjoying, traveling just as much, but there's a lot less stress. We've adapted to this new lifestyle. We've learned a lot about each other -- what to do, what not to do, what makes each other mad, what makes each other happy. I feel like we're finally just in a really solid place, in a good place maybe to start some wedding planning."
"It's a good point," Higgins agreed, as the two will continue to work on their relationship off-camera, and making cameo appearances on Happily Ever After?
The Twins: Happily Ever After? premieres Monday at 9 p.m. ET/PT on Freeform.