Hummm... Me and my partner got 20 years difference... And it never bother us at all... Not even other people's opinion about our age gap... I think the worst opinion toward us is not our age gap but our status...(bcoz we are both separated) its more on between us, how we treat each other... He been patient with me and very supportive... I wouldn't trade my relationship with him with a younger guy who have no sense of responsibility and backbones.
So as long as you know what you feel towards each other I guess nothing really matter outside your reationship