Thistle
To see thistle in your dream represents your need to feel protected. You are putting up an emotional barrier around you and as a result, pushing the people away.
Crab
To see a crab in your dream signifies you perseverance and tenacity. On an extreme note, you maybe be too clingy and dependant. You are hanging on to a hopeless endeavor or relationship. Alternatively, the dream may indicate that you are trying to avoid some issue. You are being evasive. Crabs are also symbolic of your irritable personality, as in the pun, being “crabby”.