taking Tamoxifen, is this pill going to affect the wife's sexuality?

Wife has been on the medicine since about 1 year now and since then but, I was told never to touch her now that she is on this medicine (or even before when she found out she had Cancer.  Does this mean that I am out of the picture, or does the medicine make her think this way, is it cause she does not feel like a full woman again, or is it that the spouse is just going to have to suffer for her and himself (not having to be sexual again with her)?  I just wish to know more info on this medicine, actions with it and how long is this for, for it has been some time now (nothing sexual happening, for real) and I am concerned.  I am just lost about all of this and what is going on with her.  She has been through alot and i am there for her but, that when it is all over.  Her Cancer of the Breast (both removed) has been in remission but, then now what is going happening?