At cat is better than a man.... purrsuasions.

Dear George,
I am concerned about my human, Denise. For a week or so she has been off-hand and uncaring towards me. She arrives home late after work, often smelling of alcohol. Last week there were two occasions when she failed to come home until the early hours of the morning. She smelled of male human - you know, that pungent male smell so different from the pleasant female smell. She greets me as if I was no longer the centre of her life. She does her household duties of cleaning the litter tray and putting out more food in a hurried and careless manner. She spends a lot of time vocalising in to the phone in a meaningless way and far less time vocalising to me.
How can I put right our relationship?
Hobbit.
Dear Hobbit,
In normal circumstances most human females know that a cat is better than a man - more graceful, more agile, taking up less space in the bed, and much much cleaner.
But I am afraid your human is showing signs of being on heat. In humans this isn't the monthly physical reaction that we cats understand, know and tolerate. (How much easier it would be if we could just spay them!) It is an emotional thing. Humans, unlike cats, are eager to mate throughout the year. They have no proper seasons. Instead of coming on call (the correct term), hastening off to the nearest group of males, and having a night on the tiles with several of them and getting it all over quickly, humans have a much more drawn out mating ritual.
The likelihood is that Denise has met some male that she fancies. The return in the early hours of the morning means she has spent the night with him. At least she has the good sense to come home, shower, dress and do her household cat duties before leaving again for work. And at least she hasn't given him a home.
What can you do about it? You need to counteract this with a mixture of guile and firmness. Treble your normal greeting rituals. Greet her with loud and pathetic meows. Rub all over her. Crawl all over her. Roll on your back. Generally give the impression of a cat who has suffered intense loneliness in her absence. (Yes, I realise you have probably had a nice day visiting the neighbouring pensioner who feeds you on the sly but she does not need to know this.). Leave some of your food uneaten. Give an unending number of sad looks towards her. You know the score.....
It is a worrying time for you. I will keep my paws crossed for a happy outcome.
Love George.