The 25-year-old set designer - who met Christina while filming her acting debut in 'Burlesque' - was arrested on suspicion of drunk driving in the early hours of March 1, but police have now dropped the charges due to a "lack of evidence".
A statement from the Los Angeles County District Attorney's office read: "We rejected the case on Friday (15.04.11) due to a lack of evidence. No charges will be filed."
Christina was also arrested on the same night for public intoxication and taken into custody, and although Matthew initially registered a blood alcohol level of 0.09, just 0.01 above the limit in Californian law, it was not backed up by an official result which read 0.06.
According to reports at the time, the 30-year-old singer - who recently completed her divorce from husband and father of three-year-old son Max, Jordan Bratman - was "extremely intoxicated" and "unable to take care of herself".
However, she laughed of the "hiccups" in her life, recently saying she had "obvious setbacks" but was "getting through".
She said: ""I can laugh about my own hiccups and my own experiences in life because I'm getting through it. But I get to share these experiences with these people and I get to say not every performance day is going to be a great day.
"In light of the past year, there have been obvious setbacks. I've gone through a really hard divorce, and anyone who has gone through a divorce will speak about how hard the Journey is from start to finish. It's a life-uprooting time and there have been hiccups along the way that unfortunately the whole world gets to witness and judge."
It's difficult to imagine a more outrageously camp movie than this glittery romp, and fortunately...
Ali is a girl who's desperate to break away from her small-town life. Seeking a...
Watch the trailer for Get Him To The Greek When Aaron Green lands a job...