Advice? Ideas? Is he cheating?Just need some support!

Hi all, warning...bit of a long rambling g post!

I've seen time and time again that this is a community of supportive people, but I'm also a little apprehensive of those who arent entirely helpful.

Right...where to start. My husband and I have been together just short of 10 years and married for 4. We have a 2 year old and I'm currently pregnant with no2.

We are like everyone else in lockdown so I fear this has magnified any issues I think I see. In the last few weeks he has become more and more distant, less affectionate, refusing sex and making passive aggressive comments. Now I'm not saying I'm a delight to be around, this pregnancy has been tough! So so different from the first!

Anyway, I digress. He has now started sleeping on the sofa most nights- he says my pregnancy pillow takes up too much space (,we have a king size bed) or more recently that he is just so tired he falls asleep on the sofa. I'm quite hurt by this, but he just dismisses my concerns.

So, this morning I get up with our toddler and set about making breakfast. My toddler passes me my husbands tablet (wants to watch baby shark for the 2345789 time! FML!). I set him up with the link and he is watching happily, then he brings the tablet to me again as he has undoubtedly pressed something which ended the video. But no. He is on the internet history (god knows how he got there!).

There clear as day are my husbands log ins to 'onlyfans' 'tumblr' and some other sites. I click on tumblr and am confronted with a lot of naked women and video clips of people having sex. Now I'm no prude and dont care about prom, but it seems he has been messaging other people.

I dont want to talk to my friends about this as I'm horribly embarrassed. And if I'm honest I dont want it to be true.

My question is, how do I start this conversation? How do I not let pregnancy hormones take over? How do I insure he is being 100% honest? What do I do if it is all that it seems and be is 'digitally' cheating?

Sorry for the long post, I hope you a might be able to offer some outside views.