I had a response prepared about five minutes after you initially posted, TiddleTer. Then my computer froze. So here goes again:
I know why the SSPX split, but am still confused as to whether or not we can go to their Masses in good conscience. Could I get a really brief history over the split and whatnot?
By way of accuracy, the SSPX has not "split" from the Church. There's enough information freely available online about the Society to get the gist of it's history.
However, I would highly encourage you to go beyond that and actually study the primary sources concerning the Society, it's relationship with Rome, attitudes on both sides, etc. Read autobiographies, sermons, newsletters, actual letter (e.g.: Bishop Williamson's published "Ridgefield Letters"), etc. From there you will get a better grasp of the SSPX's past and the issues surrounding it.
At the heart of the problems with the Society, such as the BS excommunications, lies political, not doctrinal, points.
Also, real quick and unrelated, I can't see the problem with attending NO Masses if no other is available, especially given circumstances like the military faces.
If there's a decent Novus Ordo around, go to it. Saint Paul is quick to remind us, "not to neglect the assembly." We need to pray with each other, we need each other for fellowship, and most of all, we need the Blessed Sacrament. Go if the Mass is available.