What if they contracted a disease from another woman and didn't know and you contracted it?

[Anonymous]

Once you get married does it feel like though you have built this trust and some how you feel like everything you have been through and all the love that has been built...that you become comfortable and ignore signs of any different behavior/cheating. That you MAY notice but choose to ignore on a different level. Can you truly trust that this person will be faithful to you at all times. What if they contracted a disease from another woman and didn't know and you contracted it?

[Pedantic]

Well, the spreading of the disease would be a pretty good way to know that they have been unfaithful. I think it MAY depend on the disease we're talking about here... if it is only transmitted sexually or if it can be transmitted through more innocent means.

I can't say I've ever heard of people getting stuff from public restrooms or drinking fountains. I think you have the evidence you are looking for.