Can a mistress claim maintenance from her married lover?

[nhs84]

If a woman has been having a relationship with a married man for 20 years, can she claim maintenance from him?
The married man constantly said he was going to leave his wife but needed some time to figure out finances and wanted his daughter to finish school. Then it was when she finishes university, etc. He has been stringing her along for 20 years and every month will give her money for rent, food etc.
Suddenly after 20 years he claims he can no longer pay.

Does the mistress have any rights to claim maintenance as they have a defacto relationship and he has set a precedent?

[Dave A]

In an effort to stop this topic sliding even further into the gutter... the OP asks a serious question.

There is no mention of a child. If there was, I would know the answer as I have seen plenty of instances of men being sued for maintenance of their out-of-wedlock child by the mother of the kid.

There is also no mention of cohabitation, and no mention of cultural practices that may establish a customary marriage.

The long standing financial dependence is the only cause presented and the answer will be a matter of law. Outside of Section 37c of the Pension Funds Act (which deals with disbursements of death benefits to dependents), unfortunately I have had no exposure to such a situation to draw on to give even the slightest indication or clue where to look.