Are Demi Lovato & Wilmer Valderrama Back Together?

Demi Lovato may be locking lips with Naya Rivera on Glee, but in real life it seems her heart has opened up again for ex-boyfriend Wilmer Valderrama.

The former couple sparked more relationship rumors after they were seen holding hands during their visit to a Halloween Haunted House over the weekend.

The X Factor judge was barely recognisable in an all-black ensemble and a hoodie covering her bright blue locks, while the former That '70s Show star decided to ditch an incognito look and strolled the park in a T-shirt and jeans. The pair and their pals arrived at the theme park with some friends around 10 p.m. and stayed until it closed at 2 a.m.

Lovato, 21, and Valderrama, 33, split in January 2012, supposedly due to their age difference, but since then they have sporadically been seen spending time together.

Lovato's outing with Valderrama follows shock claims made by Australian DJ Ruby Rose, who announced she had a lesbian fling with Lovato on Twitter.

The scandal began when Rose declared in a tweet (which has since been deleted) that she was taking a "break" from social media after being "attacked" by Demi's friends for being a "scorned ex-lover.".

"Think ill take a few days off social media whilst @ ddlovato's friends attack me for being a 'scorned ex-lover' get over it !! I liked the hair," she tweeted.

The self-imposed social media ban didn't last very long as Ruby soon took to her Instagram account to claim that she 'd slept with the 21-year-old singer. "Im like the one person demi has slept with that didnt seel on naked photos of her so eff off," she wrote in a photo comment - referring to a recent nude photo scandal in which photos of Lovato were allegedly being shopped around, supposedly by a female ex.