Your friend may try to be a good little trooper and do everything they require...which is go the the meetings, making sure the elders can see you underlined your watchtower, and of course you can't be sinning anymore. What will happen is your friend will feel real good about her relationship with Jehovah and feel she has paid her debt and then submit a letter for reinstatement.
This is where she will realize its nothing but a bunch of men who probably have remedial jobs and love the power they have. Your friend will be shattered when they tell her she has not done enough and "for the good of the congregation" they will say no to her reinstatement. She will feel confused because she will be certain Jehovah forgives her and would want her back...and if she does study a lot (hopefully not just JW material) she will see that Christ would never have disfelloshipped her to begin with. This is when she will throw in the towel, because she will see it for what it is. I will also tell you if she was having an affair with a married brother and his wife was pregnant she is looking at 2 years at least...even though they say there is no time limit how long one is to be disfellowshipped...there is depending on the sin and if its with someone in the cong.
Just search for threads on here about df'ing and they will give you the reasons why disfellowshipping in not scriptual. It will may take a while before it all sets in and realize's she is being shunned, hopefully she will research why this practice is wrong.