How do you explain to someone, especially someone you love, that some of the things they do aggravate you?
May they eat like a pig, or snore like a rock being dragged down the road. Maybe they talk too much, or too little. Or maybe the problem is just you.
In most circumstances, we love who we love because of the little things they do. However, if new habits become bothersome, communicate with them. Never just deal with it. Never allow something that they may not even know they are doing to ruin your relationship.
Little things mean the most.