My situation is very veru similar to yours. The decision you make is only YOURS to make. If you don't mind living with the knowledge that wts is a fraud and being a part of an organization that decieves and your friends are conditional friends that is your decision. If you want to know who your true friends are then you will leave and at that point you have to be able to face the reality of those so called friends who will ignore you as they pass by or who will no longer answer your calls and that may go for your inlaws as well.
If you plan to disassocite discuss this with your wife and how will your inlaws affect your lives. If you stay be careful how much you tell the elders or sooner or later they will take wts side and you'll end up in a judicial commitee. My congregation had "good" friendly people and that included the elders but when I decided to leave the cult that's when these "good" people proved to be nothing more than false friends. I personally don't need these type of people in my life. My wive's family still talks to me but that may be only because they want access to my kids as I would stop that the day they shun me. My wife still goes to meetings but not in service.
Make sure you and your wife research the wts deeply because if you disassociate yourselves and you don't do thorough reseach now, you or your wife may regret leaving the cult and will return in the future out of guilt. Read Carl Olof Jonnson's book "Gentile Times Reconsidered" which IMO is on par with Ray Franz' book. Excellent book as to why 607BC is not nor could it be a date for fall of Jerusalem which is the pillar or 1914 nonsese.
Also here are some links of old wts publications that you may find informative as you do your research:
http://www.archive.org/details/WatchTowerBibleandTractSocietyofPennsylvaniaWatchTowerpubs_0
More wts old pubs can be found here as well as child abuse court document which wts payed out of court. These documents are quite upsetting and very sad to read.
http://www.watchtowerdocuments.com/downloads/
Here are scans of Brooklyn Eagle clippings that I made into pdf that dealt with Russell which also include quotes from court trials between russell vs Brooklyn Eagle newspaper that reveal that he had a holding company and owned other business interest while wts president. Also reveals a bit of the scandel of Russell and a female he had living at his house which played part in his divorce and others.
http://www.archive.org/details/1909-1916BrooklynEagleNewsOnRussell