Toys can help and there are some really good ( but unfortunately expensive) sex machines in the market, I have two, one is called Sybian, its like a horse saddle its possible to put dildos with different sizes on it, the other one ( I do not know the name) is more mechanic with diffent sized dildos which go in and out, I use them when my black lover is not available and I‘m in the mood not only for oral sex but for penetration, these machines give me always multiple orgasm (hubby is the machine operator -LOL), maybe this would be better for your wife then your 5,5 penis