Wife was sending naked pictures of herslef to a stranger

Hello there, I would like a little advice please.

My wife and I have been married for 5 years now. We have an 18 month old son and she is 4 months pregnant with our second child.

We have a very healthy love life, and the only issues we have had up till now have been the domestic duties - which she never seems to be able to grasp.
I work full time and work away very regularly, I am not the kind of man that expects to come home sit down and be fed while she runs around waiting on me. However I do expect for the house to have been kept clean, as clean as it can be running around after an 18 month old anyway. But all she does is sit and watch tv, playing on her phone. She is an amazing mum when it comes to communicating, playing and caring for the little guy, she just can't keep him clean and dry all the time.
I have tried to support her and get her to understand the importance of keeping the basic hygiene of a house up to scratch particularly with the little one running around. But it wasnt getting anywhere so last week I suggested we looked into counselling to discuss this.
My family and pressuring me to do something about it, we never have people around and we can never entertain due to the state of the place. My wife's family do not talk to her about it, they just come round and go to the shops or restaraunt as quick as they can - I feel that they should be telling her. I, on the other hand, have just become the nagging husband who never has anything positive to say to her anymore (her words).

So anyway, last week a couple of days after I sent her the info for the counselling, to which she never responded I stumbled across some private chat she has been having in her Twitter account. I had no suspicions at all, I was simply using our old iPad of which she was the last one to have used Twitter with.

I was shocked to find that she was courting a stranger with direct messages using explicit language and requesting domination. There were gaps in the chat where it appeared she had also been sending picture messages upon his request. What worried me further is that it was clear that my wife was the aggressor in the conversation as she was posting 3 or 4 lengthy passages in relation to his short three word responses.

After lifting myself up from the floor I thought it best to just confront her, and so I did. I should add that we had a good sex life that explored almost all the options that two persons could explor, and she was very aware of my attraction to her as she was always sending me pictures as well.

Her explanation is that I am not home enough and she need attention, she needed to feel beautiful. I had intercourse with her almost every night and always told her she was beautiful, but she states that I have to say that as I am her husband and that she needs to hear it from someone else? I am not sure how to deal with this?

She has tried to explain but says she does not know how, she still want to be with me. She has agreed to go to counselling.

I feel like I have had my heart pulled out, and I trusted my wife so much, I never even considered this as possible. She is incredibly attractive and has a great figure - I felt very lucky to be seen with her. She now has her second baby bump and is blaming the change in her figure as the catalyst for her need for attention and tells me it was just her own digital fantasty and that it would have never been physical.

She has agreed to go to counselling which I think I owe it to my son and the bump for us to try as well.
What I am finding hard is whether I will be able to trust her? I also don't want to label her as unfaithful if it truly would never have been physical and if she thinks she was just playing stupid games.

Does a woman sending requested naked pictures of herself automatically means she would have committed to a physical relationship?
Or am I possibly overthinking it due to the way she was perusing him?

I don't want to make this worse by harming her with my 'what ifs?' either, I'm still, in love with her and my gut instinct is to protect her from harm!