Maybe I'm too cynical, but isn't the whole separation thing a little, errm, convenient? Then again, if he has stitched her up, you'd expect nothing less than a little domestic froideur.
Trouble is, the truth isn't important - the overriding belief will be that she has resigned from her family to spend more time with her ministry (Copyright everybody). The whole thing is still rather messy and there may be more to come out. I'm not sure that this will save Tessa.