Not sure about your touring experience and with your backcountry experience.
Also, 50 miles/80 km is not very far in remote parts of the West.
There are ACA routes with more than 80 miles/130 km between services.
And if you make your own routes, possibly further.
July 7 through August 20 is an ideal time for touring in the West.
That is the driest season for the Pacific Coast, but with this winter's rain, fire danger should be low.
Same goes for the Cascades and Sierras - excellent weather and low fire risk this year.
The Southwest and much of Nevada and Utah is usually extremely hot then.
But the Northern Rockies are beautiful - covered in wildflowers.
One of the issues is the amount of time it will take to get to the start and finish point.
You will have more options if you fly from Rome to Chicago -
Since Chicago has more connections to the West than eastern cities like New York.
If you can do a tour in both the U.S. and Canada there is a fabulous option -
Riding from Salt Lake City to Yellowstone to Glacier and thru the Canadian national parks.
Some of the finest riding in the world.
There are plenty of services and you will bump into other riders -
I think that might be important for a woman riding solo.
Another option is to ride from Santa Fe, New Mexico up to Glacier N.P.
This would keep you in the U.S. entirely.
You could start with the ancient Puebloan cultures of the Southwest, like Taos,
Then take in the parks of the Rockies in Colorado, Wyoming, and Montana.
Both of these can be all pavement - usually with low traffic -
Or you can include some dirt road options depending on your wishes.
Here's a journal with a section where I road north from Santa Fe to Glacier -
You can click for additional pages all the way up to Canada -
So it really covers both routes I outlined above.
The all-U.S. trip would be about 1500 miles / 2400 km or 400 km per week - molto probabile.
The U.S.-Canada trip would be also about 1500 miles / 2400 km.
That would give you plenty of time to explore or hike.
Best - J
Photo - Lake Josephine, Glacier N.P.