@shellzxx I am so sorry this is happening to you. He has been very dishonest with you.
BigusBumus "He is having casual sex with others (its irrelevant whether they are male or female I think" I know that this is a popular view, that it doesn't matter who the person is. But to some people it really does matter. So OP if it matter to you that your husband has been trying to hook up with men, then that's fine.
He's cheating but he is also lying about himself, presumably the OP did not know he may be gay or bi, and he himself didn't know either. So the OP has every right to be upset about this aspect of it.
Is he has actually had sex with these men, or is this just flirting/messaging etc? Either way in your shoes I would not believe it is just messaging, I would get checked out for sexually transmitted diseases whoever he has cheated with.
His attitude to you sounds just horrible and cruel, "he always turns arguments to me and it's all my wrong doing." and "But has said he done this because we were distant" He is trying to blame you because he is sending explicit photos to other people!
Please get a good solicitor and make sure you your ducks in a row as said above.
Yes, it is a new year and this is an utterly shit start to it, but at least you know. You can move on. Please do get some counselling for yourself to help you move on, in time. I am sure this kind of thing is very upsetting and I think you will need support. 