Both can hurt but it can depend. But, I believe mental abuse hurts more than physical abuse. Because it takes a total toll on your mental health. Such as triggering memories or recalling traumas. It can even damage your self-esteem or develop a long-term mental health that can take years to recover. It hurts more in a way that affects your mind traumatically. For example: you broke your arm, but it can take weeks or even a month to recover. But if you were to suffer from depression that’s something that affects with our emotions traumatically and this hurts more in a way that physical cannot. I hope this helps
Just be friendly, kind, helpful and a good friend. This will build friendship leading to a person trusting you more. Maybe share a smallish secret with them as well.