should I feel bad if my current boyfriend cheated on his ex gf to be with me.? Keep in mind she was demmanding and very toxic

If a relationship is toxic then the correct thing would have been to end it rather than find a replacement but love can at times find you in the most mysterious ways. I was always bought up to understand there are 2 sides to every story. Have you witnessed this behaviour? Have you considered her behaviour a result of his? When someone tries to hold on to a relationship it can result in some paranoid behaviour and in time she will come to see that and possibly realise that this behaviour pushed him away. If he’s a kind and loving boyfriend don’t feel bad

I believe that cheating is and will never be the answer. Since it leaves the one who is beeing cheated on to believing there is something wrong with them or that the person they were with was a horrible person. Maybe they should solve this by other means like talking, and well, if she doesn't understand then she will have to spend some time alone thinking, but your boyfriend and you will have your consciences free and you two will be able to stop thinking about her and not have to hide your relationship anymore, what will be very liberating.

This is definitely a tricky situation and I can understand where guilty feelings may come in here. I would say the fact that you are concerned about this at all shows that you are very conscientious individual. Being with someone who is demanding and 'toxic' can be very difficult and so it may be worth having an open conversation with your boyfriend about how he feels about the situation. Realistically he may be feeling bad about the situation as well and may need help with those feelings. Open and honest communication is key here. Whilst you are involved with your boyfriend your involvement is not directly with his ex-girlfriend so try not to be too hard on yourself.