I made a mistake, what do I do now?

I‘m dating my bf for 1,5 years now and things have been quite rocky throughout but we always chose each other again. Lately we haven‘t been intimate (not just sexually but also emotionally) at all and I haven‘t really felt seen or heard by him. We‘ve been going though a lot of health issues in our families and it‘s just been overwhelming for me.

Now I have this friend who I get on with well and we study together and share friends. Every time we all do things together we gravitate towards each other because we have a very similar energy. Yesterday we all were at a birthday party together and somehow he tried to kiss me, I didn’t let him. He was close to me throughout the night but I never kissed him or else. At the end of the night I was pretty drunk as was he and he accompanied me home to make sure I got in safe. He came up to wait for his taxi and we sat together on my bed. I was so sleepy at this point that I just lay down and he did the same thing- we cuddled kind of and he kissed my cheeks but I didn’t reciprocate and was half asleep as he massaged my back, then I talked to him about how I thought of us as friends and nothing more- he agreed with me.

I feel terrible now even though I didn‘t actively do anything but I let my friend cuddle with me and try to kiss me. I know for sure that nothing like that will ever happen again and I will make sure it won‘t. I feel guilty but I know if I tell my boyfriend especially right now as there are so many really serious health issues we‘re dealing with it will make our lives (and his health) so much worse.

Is it okay if I just deal with this by myself and learn to strengthen my boundaries and also make sure something like this never happens again? Or is it worse if I keep this to myself?