like banging one's head against a brick wall
like talking to a brick wall

After a very long conversation, I decided it was like talking to a brick wall.

I've talked to him about this, but it's like talking to a brick wall.

I did send the council proof of the colour that it was when we bought the house, but it's like talking to a brick wall.

I even told him how I'd come into it, but it was like talking to a brick wall.

Besides, he said, "It's like talking to a brick wall."

Thats like talking to a brick wall, Peter muttered.

I repeatedly asked for him to be properly assessed by an education psychologist, but at times it felt like talking to a brick wall.

I always hear people say " teenagers just don't listen, it's just like talking to a brick wall".

"I complained, but it was like talking to a brick wall," John McCarthy said in a telephone interview.

It was like talking to a brick wall . . . so I took out the sledgehammer.

"We felt that all the time it's been like talking to a brick wall - in talking to them and sending letters - we've got nowhere," he added.

"I tried for a long time to straighten it out and it was like talking to a brick wall," Price said of her discussions with the Census Bureau in recent years.

But for ten years I have been putting the case for this directive to the Council; for ten years I have been advancing these arguments - and this applies to many parliamentary debates too, by the way - and it has been like talking to a brick wall.