In a January 9 post to the social media site, James declared that "I have never felt so loved! I'm the luckiest MoFo in the world!"
The "Monster Garage" head man had a highly public breakup with his movie star wife, Sandra Bullock, last year and kept a fairly low profile after news of his serial indiscretions came to light.
But by August, he had started dating "LA Ink" star Von D and the two have since been nearly inseparable.
On January 12, he wrote to her again on Twitter, saying "48 hours away from you feels like a year...you will never be anything but beautiful to me."
She replied by thanking James for "always supporting me and believing in everything I do. But most of all, thanks for being my best friend."