I am a professional painter that owns my own business and you are doing one of the hardest thing to do. Do you have the wall color? The reason I ask is that some times easier to touch up the wall after painting the molding. The reason this is so hard is the caulking. Have you tried taping the wall. If you do be sure to use light strokes on the tape or it will bleed. You will have to give it a second coat. How did you do along the ceiling? One more thing, how much did you spend on that paint brush? If it was less the $11.00, throw it away and invest in a quality brush. This will make all the difference in the job. Presently I'm doing army green against white crown and blood red next to a white ceiling. I feel for you, good luck. Ron J.