Jen has never shied away from telling the world how much she cares for Bateman or publicly displaying affections to a man she's been friends with for nearly 25 years.
During his Hollywood Walk of Fame star ceremony, people could tell that Jen simply adored her friend and constant co-star, gushing, "He's a fantastic partner in crime, the most generous man that makes the world laugh and cry on a dime."
However, according to US magazine Life & Style, a once sibling-like love has turned into feelings of romance for Jen, as a source revealed to the publication, "Jen realises that she's developed deeper feelings."
The inside source continues, "Jen can't help it, she has feelings for Jason."
Although Jen is single following her split from actor Justin Theroux, 47, in late 2017, Jason is (happily) married to Amanda Anka, 50, with whom he shares two daughters.
Considering how her marriage to Brad Pitt ended, the Friends actress is wary of being involved to a married man. However, as an alleged insider told Life & Style, "It's a classic case of the heart wants what the heart wants".
According to the US publication, things came to a head for the friends over the new years holiday when Aniston agreed to join the Oz Ark star and his wife on a snowy getaway.
According to Life & Style, the threesome were also joined by actress Sandra Bullock, and late-night talk show host Jimmy Kimmel, and his wife.
Despite the crowd, the source told the publication that one night Jen and Jason were left alone and things became awkward, "Jen had had a couple of glasses of wine and they were laughing and joking - and then Jen let her guard down and leaned in a little too close."
The source continued to say how a happily married Jason resisted temptation, and promptly "left the room to find Amanda".
According to Life & Style, a rep for Aniston has denied any romantic feelings between the pair.