Did Macbeth and Lady Macbeth have a good marriage? Why?
The answer to your question concerning Shakespeare's Macbeth is somewhat ambiguous, especially if you want to be as detailed as your question suggests. Shakespeare can be ambiguous, anyway, but when you deal with a character's thoughts, drama doesn't normally deal in that area. The only time theatre deals with actual thoughts is during soliloquies. Your question, therefore, is largely an opinion question.
That said, I'll give you some details to help you form an opinion. Appearances are that they have a good relationship when they meet for the first time in the play (Act 1.5). Most productions present that scene with at least some affection between the two, and some present it with a great deal of affection. And, of course, she certainly has a powerful influence over him.
The relationship soon cools, however. After Duncan is killed, Macbeth takes over the planning and does not talk with his wife about Banquo's killing or the killing of Macduff's family. They barely see each other for the remainder of the play, and when they do Lady Macbeth is usually yelling at her husband for creating a scene. Macbeth even dismisses her at one point so that he can be alone.
Of course, a woman who emphasizes acting normally in front of others so that treacherous plots are not suspected as much as Lady Macbeth does, is more than capable of acting as if she loves her husband when she does not, so the early scene during which she is affectionate doesn't really prove anything.
Those are some of the details concerning the relationship. You'll have to study them and draw your own conclusion.
It's a very good question! I think once murder and suicide becomes involved it's harder to tell if the marriage is a good one or not, as Law & Order episodes would agree.
I'm sure however, it could be argued that their marriage was a good one insofar as Lady Macbeth wanted the best for her husband (for him to be king) and Macbeth wanted to please his wife by being king. They also worked together as equals in the murder plot, which is something that was not very common at all in a marriage of the time. It could also be argued when Lady Macbeth is egging him on to do the murders that she wants him to be his best and that she wanted that enough for him (and herself) that she was willing to get her own hands dirty as well. They were in it to win it together, for better or worse and a big part of a marriage is partnership.
However, when the going got tough, Lady Macbeth killed herself and left him alone to deal with everything, which ended badly for him as well. Also, it definitely could be argued that she wasn't so keen on the "for poorer" part of marriage, as she wanted him to be king and be rich and powerful. Also, when your marriage drives you both to murder someone, there's definitely something toxic going on!