Hi, Nick; I don't like the smell of fuel in the oil. Do you do mostly short trips? If the engine isn't getting good and hot, it won't evaporate the normal amount of fuel which is almost non-existent. If the engine is running too rich, it will contaminate the oil. If the PCV is plugged, or faulty, that can also do the same.
Has the Check Engine Light come on? If the engine is over-fueling, should show up with an Oxygen sensor code.
My oil in my 95 Subaru Impreza L coupe 2.2L AWD 5SPD is thin. I just did an oil change using 10w-30 conventional oil and it is very thin. It smells a bit gassy but when I put a flame on the dip stick it didn’t ignite. The engine has 183k miles