Sorry about the delay in getting back to you...
SJGR has done a lot of investigations down the shore and in the Cape May Courthouse area, but I can't say we have done the Motor Inn. We guarantee our clients confidentiality when we investigate.
Generally speaking, areas such as the Jersey Shore region with so much salt water in the vicinity, typically are more prone to paranormal activity. Salt water is a great conductor of energy and there's always a lot of activity reported in this region.
As for your experience at the Motor Inn, I don't want to downplay what happened to you, but possibly put it in another light to help you get the closure you are looking for... Spirits keep the same personality in the afterlife they had here on Earth. It could be this spirit didn't want anyone staying in the room they may have felt was "their space". Without being able to speak or otherwise tell you so, they may have chosen to try to get you to leave another way... by creating the sound of footsteps. When that didn't seem to work, they may have tried to scare you by getting closer and creating that "whooshing" sound. You may very well have been picking up on the feelings of anger because the spirit wanted you to know you weren't welcome in their space. However, this doesn't mean the spirit was evil.
Another possibility is that the spirit actually did welcome you and your mother, and wanted to let you know of their presence. They created the footsteps sound to get your attention and when you stayed the night with them, they tried getting closer to you. We find in our research this is what most spirits are doing--looking for recognition and acknowledgement of their presence. Again, the situation is scary, but not really evil.
If you would like to talk more about any this, please feel free to contact me directly. I'll be happy to discuss your experiences with you.
South Jersey Ghost Research