Cancel immediately. If this was a friend, reconsider the friendship, lose their number and avoid speaking with them ever again as they basically talked your wife into wasting her hard earned money and lining their pockets with a nice commission at her expense. They took advantage of her - plain and simple. No one needs whole life insurance - especially not a young 20-something with no dependents and if it was sold with the idea that
whole life insurance is an investment spiel... well, they are just absolute assholes that counted on her not knowing what a real investment actually was. The only reason to get life insurance at all is if she had dependents and in that case, term insurance is the best way to go.
If she understands nothing else, tell her this: Insurance is NOT a good investment. All she is doing is paying them a high cost for a low amount of coverage and they're taking her money and using it to invest for themselves in real investment vehicles - she's getting screwed, and royally. Insurance should never be about earning money - it's there to cover a specific need for a limited amount of time like if you have children - to provide for them until they can be independent or a spouse until they can find a job and start supporting themselves - it is NOT AN INVESTMENT AND SHOULD NEVER BE TREATED AS SUCH.
If there is any cash to be had out of canceling the policy (wow - she's paid in around 12K and might get a bit over 1k back out if she cancels... they really took her for a ride), consider yourselves lucky. But the money she paid in is gone - consider that "sunk cost" and the price of not understanding how investing and insurance actually should work. It hopefully is still cheap for the price (some folks don't figure this stuff out until they've spent tens of thousands of dollars or worse, after decades of "investing" in their whole life policies... so sad).
Funnel the money she was paying into real investments - either through a work provided tax deferred account (401k, 403b, etc) into the closest match to a low cost index fund (can post here for suggestions if you can get the plan's selections) and if none offered, open either a Roth or traditional IRA at Vanguard and place funds there. As you're both young, it would be best to try to get into something like Vanguard's target date funds (Vanguard Target Retirement 2050 Fund (VFIFX) looks good for an example) which have a lower minimum buy-in ($1,000) and you don't have to think about them as they rebalance automatically. Simple, low cost and no hidden gotchas or stupid asshole "friend" like advisers picking your pockets. ;)
Suggest you also do some reading on how the market and investing works. This is the best primer out there (helped me out more than I thought possible):
http://jlcollinsnh.com/stock-series/