Cheated on.

Just learned my long term partner who lived with me was cheating on me through the whole relationship. He had a secret girlfriend from back home who thought he was just living with friends and finishing college.. she was back home waiting for him the whole time. I feel awful for her. I’ve never been cheated on before. The biggest issue I’m facing was he was super idyllic besides the cheating. He knit blankets for me, listened to every song I sent him, payed for everything, was at my beck and call, held onto my every word. Fabulous cook, fabulous musician, fabulous writer. Shared interests, perspectives, and he took care of me so incredibly with my struggles with chronic illness + epilepsy. He has since left. I was too forgiving, he felt too guilty. Hes in love with the other girl. I don’t think he’s in love with me. He’s spending time alone visiting some relatives. I don’t think he’s coming back.
I have a very minimal support system, and as I’ve mentioned have never experienced this before. What are ways I can start the healing process and start to move past this?