I can perfectly understand your feelings there (and I share them!).
In you specific situation, one should also look at the Church practice prior to Vatican II. Even in these times, one was dispensed rather easily of the Sunday obligation, e.g. if one was too poor to afford decent clothing.
In your case, conceding obligation to attend Mass there, living more than an hour away (even though I think Church Law needs some actualizations in regards to modern ways of transportation) and the possibility of scandal to you and your family, you are clearly dispensed.
I would strongly advise to attend Mass at an SSPX chapel, if this is closer or more convenient for you. Their clergymen are better trained and their chapels have a much better parish life than most sedevacantist places.
By the way: In private, quite a few traditionalists priests admit that the faithful cannot fulfill Sunday obligation in their chapels.