Good decision on the dog.
Unless you are going to use some form of vehicle travel, I think Pittsburgh to San Diego in 3 months is stretching it for a newbie. I highly suggest you do a few short tours locally to get your feet wet. And nothing wrong with taking the train or bus to make up time or bypass the boring parts of the country,
Warmshowers us reasonably safe. Of course your mileage nay vary. One issue with warmshowers is there is no real vetting. People can leave comments but people rarely leave negative comments.
Couchsurfing on the other had can have someone from the organization certify hosts. Again not fool proof but better than warmshowers in that regard. But I am not a fan of couchsurfing in the US. Most hosts are almost overly social. It is almost like a cult. Hard to explain just say it can be a bit bizarre.
Periods? Searious? Does your wife know you are asking that question for her?
