Having sex without affection ultimately is sickening (6)
I believe the answer is:
ailing
'having' is the definition.
The definition and answer can be both related to bodily activities as well as being present participle verbs.
Maybe there's an association between them I don't understand?
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for ailing that I've seen before include "Infertile" , "Sickly, poorly" , "In poor health" , "not doing very well" , "Unwell, in poor condition" .)