Break up from toxic relationship

I’ve broken up with my boyfriend of 4 years. He’s always lied to me about female friends and met up behind my back or spoken to them a bit too much. I love him with all my heart but he’s been doing such things to me since 2015. I always forgave him and stayed. Last night I broke up with him. I feel physically ill from the separation and I don’t even know how to go about life without him. I have exams this week and I know that I should focus on them rather than the break up but those of you in relationships should know how difficult it is to lose the persons that you love. I often found it difficult to believe that he loved me back due to everything that he did to me, though we did have a few good moments. I really miss him and I’m not sure how to continue.

I asked him to not speak to his ex as he made her block me on social media so that I could not see their photos together, he also used her to try to break up with me previously (he claimed that he had feelings for her), he also met up with her on numerous occasions and did everything to hide it from me. If only he was straight up with me would I have understood that they were friends. But he lied so many times. I may have been controlling by asking him not to speak to her, I know. However I told him that if he ever hurts me again, I would leave.

Last night, I found out that they still text. And I left.

I’ve had chronic depression for around 3 years and I don’t know how to handle the break up as it’s also my first break up. Please help me someone