my partner cheated and we still have 4 months before we can see each other

So we've been dating for more than a year now, had it rough at first but worked trough it. Trust was a big part of our relation and we worked hard on it. I decided to study abroad for 4 months, i knew he wasn't overjoyed with it and i wasn't either but it's a good opportunity. It's also important to mention that I had a lot of problems with friends back home and that its was good for me to get away and work on myself.
On his side, he moved out of his family home to live alone next to his new university. this cause a lot of stress on him, and i could feel him not being himself because of everything that was happening so fast..

So I've been abroad for 5 days now, and he told me while crying that the first night he went out, he got drunk, danced and then made out with a girl. We had both agreed that we considered this cheating.

Now, he says its was a huge mistake that he wishes he could take back. he feels awful but understands me wanting some time to think. He swears it was the first time this happened and that he has neevr lied to me. We will still be apart for 4 months, so it is not really possible for us to fix this right now. so he wants me to take a break from him and enjoy myself because me figuring out what to do with us is causing me a lot of pain.

I just don't know how to feel, what to do... i feel like maybe i should take 2 weeks and think about if im ever gonna be able to get over this, or even if our relationship is worth it. He knows everything he lacked and is promising to fix them, if i forgive him...

I just feel like i lost my bestfriend and i dont want that. But at the same time I can't possibly imagine myself kissing him or more, cause i know im gonna imagine him with someone else...

have any of you gotten over being cheated? I don't feel like it exists.
what should i do? how should i feel?