I've have a pimple like knot on my neck for 2 years

I've have a pimple like knot on my neck for 2 years. It never forms a white head its a hard knot a little smaller than a pea. My wife squeeses it about once a month and the fluid smells. It never has went away for the past two years.
What is it?

[loiloi]

Do not squeeze acne spots. This will spread bacteria under the skin leading to more spots or delayed healing of the existing spot. It can also cause secondary infection and even long-term scarring.
It would be very unusual to have an acne spot for 2 years, you may wish to repost this in the Dermatology forum as it may be a sebaceous cyst or other skin problem.
Eloise.