Numerous answers exist for your question about Shakespeare's Macbeth. Opinions differ. You could say that the situation is ambiguous, there's more than one way it can be interpreted.
What the reader knows for certain is that both Macbeth and Lady Macbeth are ambitious. After the first of the predictions by the witches comes true, Macbeth thinks about the possibility of killing Duncan, as does Lady Macbeth. When they meet for the first time in the play there is at least an implied agreement that they will assassinate Duncan.
Macbeth changes his mind and tells his wife that they will go no further in their plans to assassinate the king. Lady Macbeth talks him back into doing it. She has the opportunity to do it herself, but she is unable to because the sleeping Duncan reminds her of her father. Macbeth does it.
That is what the reader knows with relative certainty. Whether or not Macbeth would have ultimately gone ahead with the assassination without Lady Macbeth is speculation.
By the way, Lady Macbeth has nothing to do with Macbeth's ordering the killing of Banquo and Fleance or with the killing of Macduff's family. She knows nothing about those until after they occur.
And the gentlewoman is irrelevant to this discussion. She simply sees Lady Macbeth sleepwalking and understands that the Macbeths must have been responsible for all the murders that have been occurring. She simply comments that she would not want to trade places with Lady Macbeth. She makes no comment whatsoever about Lady Macbeth's influence over Macbeth.
In the play 'Macbeth' by William Shakespeare, the author has Lady Macbeth 'wind up' her husband Macbeth like a toy, by exacerbating the situation where the witches appear to put an ambitious idea in his head that was either not there before, or was latent. A spark of a plan that may have lay dormant for years and never come to anything is fanned and whipped by the flames of Lady Macbeth's own ambition. When she encounters resistance she resorts to worse and worse temptations and insults to get her way. A good one she seems to find, is to emasculate Macbeth by pouring scorn on his man hood using taunts like 'art thou a man?' Eventually, the drip drip drip action seems to work - we can only guess at what would have happened otherwise.
Given all the things that Lady Macbeth says in Act V, Scene 1, I do think the Gentlewoman does not believe Macbeth would have done all of these crimes if it had not been for his wife.
If you look at all the stuff that Lady Macbeth says as she sleepwalks, she seems to be the more active and assertive. She is telling her husband to stop being afraid. She is telling him to stop acting all weird before he gives away what they have done.
So, given what Lady Macbeth says in this scene, I think the Gentlewoman would blame her for Macbeth's crimes.