In a recent blog post, Masuwaka announced that she is getting a divorce from Umeda. There have been rumors about their imminent divorce, especially after they stopped living together. Rumors of her husband's infidelity, lack of child rearing help, and lackadaisical work ethic persist, but he wrote on Twitter that he'll "take the truth to his grave." Whatever happened, it's obvious that these two just didn't work out.
On Yahoo! Japan, one Japanese entertainment industry rep gave a slightly different, if somewhat sad, reason for the divorce—namely, intrinsic character differences. "It was because in contrast to Masuwaka, who is sociable, Umeda is an otaku (geek), who was always reading One Piece at home." Oh yeah, that makes perfect sense. A shotgun marriage between two people who probably didn't really know each other very well? Less so.
One Piece: Wrecking Japanese marriages, since 1998.
離婚でバレた益若つばさの嘘ブログ [Yahoo! Japan]