You should be able to eat cheese that has been matured for 6 months or more for example cheddar, just make sure it actually is matured for that long, cheddar can be sold as 3 to 24 month. I am assuming it is 3 if nothing is specified, younger cheddar is sweeter so I wouldn't be surprised if most cheddar in your store is that young like those hamburger slices. Everyone except me in the family has lactose intolerance and are very sensitive but can all eat 6+ months matured cheese. Which is great because that was the only kind of cheese we all liked anyways.

lactose sensitivity can be different from person to person so maybe you can eat a younger cheese. Cheese that had a low lactose from the start could be enough for you or just a few weeks maturing. 6 months is just something that has always worked for us without the need to know how much lactose there are.