There are two possible reasons you may be ‘chickening out’ as you put it:
- You subconsciously do not want to put in the hours of work it (could) take to solve a problem.
To solve this, you will simply have to put in the work and do the problem.
- You are not completely at the level of silver but are good enough to pass bronze.
I think it is more of this than the previous reason. To solve this, you should start doing some harder Bronze problems, and work your way up to silver problems. Bronze problems from the years 2012 to 2015 are generally a bit harder than today’s bronze problems, and US Open problems are hard as well.
Silver is also the level when basic algorithms such as DFS start to come into play. It will be hard to progress unless you start to learn these algorithms. The USACO guide has started become a reliable source for me, and for the silver level should contain almost all topics you should need. It also provides references to problems.