run (one's) head against a brick wall

run (one's) head against a brick wall

To attempt, continually and fruitlessly, to accomplish some task or achieve some goal that is or seems ultimately hopeless. I feel like I've been running my head against a brick wall trying to understand this math equation. Some people are never going to agree with you on this, so it's no use running your head against a brick wall trying to convince everyone.
See also: brick, head, run, wall
Farlex Dictionary of Idioms.

run one's head against a brick wall

Fig. to be frustrated by coming up against an insurmountable obstacle. There is no point in running your head against a brick wall. If you can't succeed in this case, don't even try. I have been running my head against a brick wall about this problem long enough.
See also: brick, head, run, wall
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • run head against a brick wall
  • beat (one's) head against a stone wall
  • knock (one's) head against a (brick) wall
  • knock (one's) head against a/the wall
  • knock head against a brick wall
  • bang (one's) head against a brick wall
  • bang (one's) head against a wall
  • bang your head against a brick wall
  • be banging, etc. your head against a brick wall
  • be hitting (one's) head against a (brick) wall