This has happened quite a few times.
I meet a woman and go out for a few dates. Over the period of 6-12 weeks we have sex about 5 times then she starts behaving very strange. She will:
A) not initiate phone calls/text messages.
B) respond briefly on text messages
C) make last minute cancellations (excuse: I'm too tired and don't feel like it)
D) find my jokes offensive rather than funny.
E) hardly asks me normal questions like "how are you".

Basically to her I'm not a human being anymore.

To deal with such situations I usually try to end the conversation first like "I guess you are not in a chatty mood... Have a nice day.". Her response to this is a convenient message like "sorry having dinner with a friend"

I have also not contacted her for 4 weeks and still the same behavior.

theres not much you can do. she doesnt like you anymore.

Not trying to be an ass, but maybe you need to work on how to satisfy a woman?

She's clearly not interested. Game other women who will give you the time of day.

You need to figure out what you're doing wrong! it could something like being to needy or insecure. Do you really like these girl? if you don't they may detect it and know something is wrong.

Think back to when she started being off with you, maybe you can figure out what you did and prevent it from happening in the future.

_________________
"All that we are is the result of what we have thought. The mind is everything. What we think, we become."
Guatama Buddha

It could be that he did nothing wrong! Sometimes a person isn't interested for whatever reason, trivial or not. You shouldn't retool your approach because it didn't work with one person - imagine how exhausting that'd be, not to mention your new 'strategy' may be ineffectual for the next woman that comes along.

Move on she's not interested.

He already said that it has happened a few times if you read his message.

I never said anything about retooling his approach, it could be a very simple and correctable mistake.

"The definition of madness," "doing the same thing and expecting different results."
Albert Einstein

Why don't you ask her? You may be doing some easily correctable mistakes and an honest answer from her is of more value then 50 guys worth of replies from us.

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