To dream of a lifeboat represents a backup plan or secondary route to deal with uncertainty or negative situations. A way around an excessive amount of adversity. It may also be a sign that you are prepared to use simpler methods to deal with problems or difficulties if your original plan doesn't work. A safe way to walk away from your troubles. Having a backup plan or safe way to escape trouble in case someone doesn't help you in a crisis.
Example: A woman dreamed of getting on a lifeboat and having some difficulties doing so as someone almost tried to push her out of the boat. In waking life she went on maternity leave and feared getting replaced at her job when she left work. In this case the lifeboat mot likely reflected her sense of job security she got from taking maternity leave.
Example 2: A woman dreamed of having a lifeboat. In waking life she was very concerned about having an easy way to end a relationship if she didn't like dating the man anymore.