We drove cross country for 2 months last summer...with a small dog (wife and me).  We had a good time but it did get small.

We found it important to shake the bedlinens almost daily as well as sweep the main area.

We used 2-3 post max (in fact after about a week we sent a great deal of stuff back home).

The fridge wasn't really adequate (we traveled through 90 degrees most of the time) so we had 2 coolers and purchased 2-3 days of food at a time.  Ice 2x per
day was a must.  Since we are vegetarians most of our food didn't require refrigeration...it was soy based and cooked already in many cases.

We also stayed in hotels (super 8 mostly) once every 5-6 days for a relaxing shower and a day off...and air conditioning.  It really helped.

And even though my wife and I have lived together for almost 25 years...it did become stressful at times...I would not "live" in it if I could help it...but a vacation
was okay.

Good luck and have fun...

--peace--
    stu