Sometimes being difficult to hurt also makes you difficult to reach.

The same wall does both jobs. Whatever keeps criticism, rejection, and loss from landing also keeps affection, praise, and closeness from landing, because there is only one door. People who have made themselves hard to wound often find that compliments bounce off too, and that they cannot quite feel the good things that happen to them.

If you have noticed that nothing much reaches you, the numbness is likely not selective. Try letting one good thing in properly: a kind remark, a moment with someone you love. Feeling it fully will be uncomfortable, which is the evidence that the door is still there and still works.