To dream of a life jacket represents security and reinforcement while confronting uncertainty or negative situations. A backup plan or insurance that you can’t fail or be overwhelmed by a negative situation. Knowing that no matter what happens to you you’ll make it through a serious problem. Preparing for the worst or feeling that a situation is headed towards a crisis.
Negatively, dreams of a life jacket may reflect putting too much trust is something protecting you or helping you through a difficult situation. Not being critical enough of advice. It may also reflect feelings of being stupid for having trusted something.
Example: A woman dreamed of seeing a dog wearing a life jacket that was so amazing that she dropped all her belongings in a bog. In waking life she trusted the advice of a doctor that gave her a bad diagnosis which ended up making her medical problem worse. She refused to work with the doctor ever again, but then ended up having to go to the hospital to fix her problem and felt completely controlled by the new doctors.