The Scream star began dating TV reporter McLarty last summer (11) but they struggled to maintain a long-distance relationship and parted ways earlier this month (Mar12).
Arquette, who conquered his alcohol issues in rehab last year (11), jetted off to Cabo San Lucas, Mexico for a sunshine break last week (ends16Mar12) and posted a few photos and updates for fans on his Twitter.com blog, prompting speculation that the actor was taking advantage of his new single status.
The false rumours have compelled Arquette to set the record straight.
In a tweet to fans on Tuesday (20Mar12), he writes, "Just to clarify - I took a lot of pictures in Cabo but was a complete gentleman. I danced and had a sober good time. No girls for me - 2 (sic) soon".
When asked by one follower if he felt the need to speak out because of a "guilty conscience", he replied, "no but haters report lies and i speak honestly. nothing to be guilty (about)".
Arquette split from his wife Courteney Cox in 2010 but the two remain friends.