Demi Lovato's joy at being bridesmaid for best friend

Demi Lovato has shared a heartfelt Instagram post after acting as a bridesmaid for her best friend Jenna Schubart.

The 26-year-old singer-and-actress was overjoyed at taking on the role for her pal of 23 years, and she insisted Jenna and her beau had the "perfect wedding" and praised them for being the "perfect couple".

The 'Sorry Not Sorry' hitmaker shared two selfies, showing herself posing while wearing a black long-sleeved crochet bridesmaid dress with embellished lace detailing all over, which she paired with a dramatic smokey-eye and baby pink lips.

She captioned the photos: "I was a bridesmaid yesterday for my sister / former babysitter/friend of 23 years. I love you @jennaschubart. What a perfect wedding for a perfect couple!!"

The 'Camp Rock' actress surrounded herself with family and close friends at the glitzy bash, and shared a video of her mother, Dianna Hart, laughing and dancing at the wedding reception as well as an adorable snap with her younger sister Madison De La Garza, 17.

She simply captioned the image: "Baby sis".

Demi - who was hospitalised following a drug overdose last July - has also been using her social media to joke about her new-found sobriety, and delighted her fans when a post on an Instagram account caught her eye.

The meme showed a group of friends toasting around the table, with one of the women holding an imaginary glass, and had a message printed above which read: "When you're all about that new sober life but still tryna hold onto your old ideas."

The image, which Demi 'liked', was captioned: "One of these days I swear I'll actually resemble a real human person."

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