I hear you, Chaz. I had a bad patch, too, after I moved and my first teacher died. That lasted for almost ten years, and being on FreeSangha really helped at that time. Eventually, I connected with a sangha again which has required considerable travel.
It is always good to go back to the foundations and training in vipassana/Theravadin traditions can be of much benefit. Then, one can engage in Vajrayana again with more meaning.
I strongly recommend going on with the ngondro, even if there are some lineage issues now. Ngondro is an extremely long-term investment in improving one's mindstream. This is accumulation of merit and the more it is done the more it causes the outer teacher to manifest. If prostrations are physically hard, Vajrasattva is really, really helpful. Just do a little bit every day.
Now, look who is talking -- here in the Gelug, we are quite laid back when it comes to the ngondro, so I didn't take any of them seriously before. Having to work extra hard now!
Respectfully,
Gibbon