Guarantor problems!

[PeXy]

Not sure if this is the right place for this, but here goes. My partner was a guarantor for her previous boyfriend 6 years ago (stupid I know) then out of the blue we have had phone calls and letters from the finance company demanding she pays (as he can't) or she will have to go to court and be blacklisted. Is there anyway of going after her ex-boyfriend for the money if we pay it?

Anyone had any experience like this?

Jim