So you see a guy on line 3 So you see a guy on line 3 - is that a sign of the wife cheating?
No, I assume that is the husband. : )
Unless you are the husband, but as you didn't say "I'm getting married" I'm assuming someone else is getting married and you are asking for them. And yes I'm aware you try to set him somewhere else.
Well, I do understand that you can't go into details due to obvious reasons, however please share the knowledge as much as you can without going into "secret stuff", as possible 
I can, but there is a reason I keep recommending AK course. For example here there is so much going on all of it fascinating and the only thing I can say is that Self line is on black tortoise and line 6, so somewhat out of the situation and with questionable motivation.
Something that doesn't seem to fit the groom. But even this can't be taken fully, as there are details to it as well. And there is always a possibility he just doesn't want to get married, but there are other reasons I'm taking the guess that isn't what is going on.
Overall, the "secret stuff" is related to Aks material and its too fundamental to a reading at this point, without it there is only some very limited ideas and stuff left. We have good material in English now, we got people in the open as far as we could,if someone wants to learn how it actually works the path is through AK in my humble opinion. And this isn't advertising, its just the only logical next step if we want people to keep learning.
If I take your setting as the right one, let's look: the Asset line moves to Parent line. Parent weakens Asset. Furthermore - this is a clash hexagram, that is also a bad sign. The self line is very weak, and Object controls Subject (Wealth - Sibling), which is also bad for the marriage.
Could you comment on that if possible, please?
This can be valid if we take the Husband being on the Self line. I have many doubts on that(around 7-8 more reasons more then what was mentioned, all related to what is the right Asset, how the situation change depending on the right Asset and stuff like that) Since you asked and I have no idea about your view to the situation, how you position stuff or what the actual situation is, all is just guessing, obviously.
Overall, we are in transition state in my humble view. The community that is interested in WWG in English. Many of us shared openly what we knew for many years and it is enough to get some surprisingly good answers from time to time, while always having the risk to have a miss without understanding why and without a good understanding of what is happening in the whole Hexagram most of the time. Also with no idea how we can affect the situation at all.
Then AK showed up and in his courses provided depths to the system that go way beyond anything we have,. At
this point, it seems unethical to keep posting so limited stuff then what could actually be used without mentioning it.
So I'm open to try to help, but you can't learn it in the open, there is too much we didn't knew even just on the first steps there. For everythint that I may mention, because I knew its already out, there will be 4-5 other important relations and factors that will be missing. How accurately one can read with that?
And in this case, the reason I'm saying I would expect a good marriage even though still a guess, as the circumstances of another person asking are limiting, are based on rules that doesn't exist in the open, yet are vital in some cases.
I remember some years ago was explaining to Ren that in my view, there is no way we could use 2 Images of something as in WWG, there aren't that many reliable sources of Images. That seems so silly now... Yet its a good pointer to where I was at the time and how far the path ends in the open.