I have the same problem and it pisses me off too Marcella.
Two tricks to minimize this pain is to create a copy of your shape with smaller breasts and save it within the outfit so you only use it when you wearing mesh tops (I also have a 3rd copy with smaller butt too).
The other one is to create your own alpha layers. This one is not so easy but sometimes the results are better, specially when the creator makes too mush body parts invisible (like between legs, cleavage, etc) to ensure it fits for everyone.