Maroon 5 frontman Adam Levine has reportedly split from his girlfriend. The sexy singer is said to have ended his relationship with model Kelly McGee, who featured in the band's 'This Love' video, due to his busy work schedule. A source revealed to Britain's Mirror newspaper: "Adam's really upset as they were together for a long time. But he's so busy now that he doesn't have time to wallow." Adam recently confessed he considered ending his relationship with Kelly after six months - because it was getting too tough. He told Britain's New magazine at the time: "Kelly and I have had our problems. But we're still together. It's been over a year-and-a-half and we take it day by day, but love is tough. The only kind of love that's easy is the first six months. "I was tempted to move on after six months with Kelly, but you have to weigh it up. Anything that requires effort, patience and sacrifice. You have to deal with troubles and conflict and turn it into something really amazing and rewarding. If it works out, it works out and if it doesn't, it doesn't." However, he recently revealed how Kelly wasn't happy when he kissed his favourite actress, Kelly Preston, in his video. Kelly was furious over the passionate love scenes between the two in the video for 'She Will Be Loved'. He said at the time: "I admit Kelly Preston is a woman I would love to make out with in real life. My girlfriend refuses to watch it and was less than happy when I came home from the shoot."