Two-time U.S. Open champion Bryson DeChambeau and his girlfriend, model Mikayla Demaiter, are still going strong since the pair started dating earlier this year. Us exclusively obtained a photo of the couple, with a source saying that the two are very happy together and “getting serious.” The picture was snapped recently inside DeChambeau’s home in Texas. The insider said Demaiter, 26, was in town staying with the golf superstar and has been spotted regularly in the Lone Star State with DeChambeau, 33.  Things are progressing so well that the couple’s dogs are even friends...