Demi Lovato says goodbye to those she lost in 2015

Demi Lovato closed out 2015 by remembering those near and dear to her she lost during the year.

The 23-year-old Cool For the Summer singer had a tough year in among all the success she enjoyed in the charts, and took to Instagram on New Year's Eve (31Dec15) to post a special tribute.

"As incredible as this year was," she wrote, "this year was also extremely rough. Filled with some of the highest highs, I experienced some of the lowest lows.

"I said hello to a lot of amazing experiences and said goodbye to many that I love but everything happens for a reason and my skin got a lot thicker this year. I learned that no matter how painful things can be, things do get easier and time really does help heal all wounds."

Telling followers she felt "so blessed to live the life I do, with the people I love by my side", the recovering self-abuse victim, revealed she is hoping 2016 "will be a bit lighter with more hellos and less goodbyes".

"I know I'm stronger than I was a year ago," she added, before urging fans to "cherish the moments you have with your friends and family, take too many pictures and always find the humor in things. Life's too short for negativity and drama.

"Spread love, not hate and most importantly be grateful... We love and miss you already Spawn, Papa, Uncle Billy, Chris, and Buddy."

She also posted a montage of all those mentioned.

Spawn and Buddy are the dogs Demi and her boyfriend Wilmer Valderrama said goodbye to in 2015. Spawn died the day after Christmas (26Dec15).

The Heart Attack singer shared the sad news with fans on Instagram.com on Sunday (27Dec15), posting a photo of the pooch nuzzling her face.

"I miss you so much already beautiful boy," she wrote in the accompanying caption. "When I first met you 6 years ago, I was intimidated by your size and your strong presence... But as I got to know you, I learned you were just one big teddy bear. One handsome teddy bear that's for sure.

"I'm going to miss the way you greeted me at my car every time I came home or simply when I stepped outside. I'm going to miss the way you were so protective of (other dogs) Buddy and Batman and never got annoyed with them when they were excited hyper puppies. I'm going to miss the way you would nudge at my hand if I wasn't petting you.

"I'll even miss the way I'd need a Benadryl (allergy medication) every time you'd give me kisses just like the way you're giving me kisses in this very picture. All the sneezes, the runny noses, even the occasional hives... They were all worth it with you."

Demi rang in 2016 in New York, where she was among the performers taking part in TV marathon Dick Clark's New Year's Rockin Eve with Ryan Seacrest.