Friends this story I am going to tell you is related to a very scary experience I had in the year about 2001. But before that I never used to think that something exists beyond our imagination which does exist and to say the truth which I experienced is a reality.
I was coming back from visiting my close friend when I saw a old woman sitting in the garden in front of our house. I thought it must be some visitor to the garden. I started walking towards my house when suddenly my attention once again went towards the old woman. She turned her head towards me and started saying "come here my boy", I want to tell you something. I thought she was pulling my leg or maybe she is mad and was laughing at me. I thought better to ignore her and walk home. But suddenly something made me look back towards the bench on which she was sitting and no one was there. I realized quickly that something was wrong with that woman.
I ran like anything and quickly came to my home. I had fever for almost three days. I never spoke about this to anyone as I know very well that if I spoke about this to anyone they would laugh at me and tell me that I need a psychiatrist Or should have been admitted to the mental hospital. I told about this to some people but they all laughed at me and suggested what I told above about. But what I have spoken is true. I know people laugh at me but what I have experienced is hundred percent true. If anyone laughs at me it is their point of view. But if anyone trusts me just explain me about what I experienced in detail.
In my opinion, it's very difficult, if not impossible, for anyone to explain what is wrong in that garden. There's not enough information in your narrative to reach any accurate conclusion.
You could start by researching if what people say are facts or only unfound rumours and urban legends. There has to be, somewhere, a recorded history of the area.
You have stablished that your "father has lived here for almost seventy five years." and he "says that there were huge ponds and lakes there".
Did he see the lakes and knows what happened to them? Did they dry out by natural causes or as a result of a man-made project? Does he remember if a woman that resembles the one you saw ever lived in the area during the time he has lived there?
Are you aware that some environmental factors, like electromagnetic radiation, pollution, etc., can affect people's mood? Would it be possible that, what you call "negative energy in the garden" is not necessarily paranormal, but the effect of exposure to something mundane?
As I have already said, it's hard to know what may be wrong in the garden without knowing anything about it. You are welcome to share your experiences in this forum, but keep in mind that when it comes to the paranormal, there's nothing written in rock and we are here not always to find answers, but to be heard and to know that we are not alone nor crazy after experiencing something unexplained.