The 39-year-old actor dated the 'Cool for the Summer' singer for six years until 2016, and Demi is pleased that the 'NCIS' star has found his "life partner" in 28-year-old model Amanda Pacheco, who he asked to be his wife on New Year's Day (01.01.20), after just nine months of dating.
An insider told E! News: "She's happy for Wilmer if he's happy. "She always wants the best for him in life and is glad he has found love. They will always be friends and have a special place in each other's hearts.
"But she also realised he wasn't going to be her life partner and she's known that for a while. She moved on from that and has been going in a different direction. She wishes him all the best though."
Wilmer and Amanda announced they are engaged on Instagram earlier this week.
Alongside a snap of him proposing on a rock in the sea in San Diego, Wilmer wrote on Instagram: "It's just us now" 01-01-2020 (sic)"
The loved-up pair were first seen together on a shopping trip in Los Angeles in April.
A source said at the time: "He definitely wants to make sure she feels taken care of.
"Even if they are just doing simple things, they have a lot of fun and are always smiling."
As well as dating 'Confident' hitmaker Demi, the former 'That '70s Show' star was previously in a relationship with actress-and-singer Mandy Moore between 2000 and 2002.
Wilmer and Demi have remained close friends after their split.
In fact, it was reported that she had been regularly chatting to her ex after leaving rehab following an overdose in July 2018.
An insider previously said: "She and Wilmer still communicate regularly. Valderrama was a crutch for Demi through her hospitalisation and visited her in rehab too.
"The two talk several times a week and meet up as well ... but it's nothing romantic, simply a supportive friendship."
Meanwhile, the pair reunited on Instagram Live last April, and it was evident at the time just how much they still care for each other.
The 27-year-old star joined her ex for a surprise appearance on his social media stream.
In one clip, Wilmer told Demi: "You look awesome, girl!"
He then playfully added: "I'm done with work on Wednesday, so holla at your boy."
Demi beamed and said she would be in contact as Wilmer said goodbye.
He added: "See you, angel. Love you!"
