cheated on ?

So I had made  a post on here last month about my boyfriend texting his ex at the time that went down we had been together for five months and today I found nude pictures of his ex that were from October 2 when I confronted him I had gave him an opportunity to tell me if something had happened I had asked if he honestly could tel me they weren't being flirty and he had said maybe in her part but he didn't return it now today when I found those pictures he admitted it wasn't in ice to and they ended up sexting he sent a shirtless photo she sent two port pics and we all know it wasn't just pictures there were words too. Idk what to do I'm so hurt and idk if that counts as cheating but I feel physically sick constantly and I know I deserve better but I also love him and want to give him another chance... idk I need some advice here ladies please