How drastic would the variation in tides be ranging from 1,500 miles to millions of miles
As the force of gravity is inversely proportional to the square of distance, the moon's gravity would be felt aat over 25,000 times stronger than it is felt now. .
That sounds like it would affect the water in our bodies and kill us.
Well, even at the surface of the moon, the gravity is only about 1.6 m/s^2. So gravity at the earth's surface would still be at least 8.2 m/s^2. A 192 pound guy would still weigh at least 164 pounds.
1500 mi = about 2400 km. By this chart, at that altitude above Earth, the gravity is just over half what it is at the surface:
Applying the same reduction to the Moon's gravity puts it's gravity 1500 miles away at the Earth's surface at about 0.9 m/s^2. So gravity at Earth's surface would be about 8.9 m/s^2. The 196 pound guy would still weigh 178 pounds.
But the oceans are a very thin covering on our planet. Increase the tides by. 25000%, and that would be ... noticeable. A 1 m tide becomes a 25 km tide.. We may still have some dry land, and we would all lose weight. The atmospheric pressure would only drop by about the same proportion (slightly more, let's call it 10% total reduction, due to the gradient), and the surface of the Earth would feel then the way being at an altitude of only about 1000 meters feels now (roughly the elevation of the lowest point in Colorado):
What would really kill us would be the cold. While the moon was completing the half of its orbit centered on perihelion, the Earth would often get less and less sunlight than it currently gets. Near perihelion, and when a "New Moon" or close to it, the Moon would block out a significant proportion of sunlight. The Moon would be about 15 deg in angular size.