I (22F) mistakenly accused BF (22M) of cheating on me. He says he want to break up.

Throwaway account. Long post, please bear with me.

Have been in a relationship with my bf for 2 years. Never had any real problems until now. He moved to a new job about 4 months ago and is being mentored into the job by a senior female employee.

She calls him after work hours too to make sure that the work is on schedule and to inform him of various responsibilities of the next day. I have been okay with all this until one day she called him around bed time and asked him if he could pick her up in the morning because of some problems with her car. I found this unnecessary and told him to not do it. He said it was okay for one day and did pick her up in the morning.

I argued with him in the evening and told him that i find her calling him outside of work to be uncomfortable. He rejected that and said she only says things about work and as she mentors him, he cannot just ask her to not call any more. This has been going on for some time. But the breaking point came yesterday.

One of my friends called me yesterday noon and told me that she saw my bf eating lunch in a restaurant with another woman. She described the woman and i was sure that it was the mentor. In my mind, i was almost sure that it was nothing but still when he came home, i exploded and screamed at him and accused him of cheating on me with her.

I shouted over him for a good 30 minutes. When i calmed down, he looked livid and showed me a photo on his phone. It was a selfie of him and several of his colleagues having lunch and it was just that he and the mentor took a smaller single table by the side of the extended one.

I apologised a lot but he said that he doesnt feel comfortable that i am getting insecure over him working with a woman. Today morning, he told me that he needed some space and went to his friend's house. He is not taking my calls any more and i want to go to his friends house to talk to him. How can i convince him that i know that i went overboard with my reaction?

Tldr: Mistakenly accused bf of cheating on me with a colleague. He is now wanting to break up with me.