AITAH if my (25) bf (27) thinks rape is cheating?

I had a situation last year with a member of family and got raped on holiday and I told my bf about it and to my surprise he reacted by crying and saying I cheated on him. I was really confused by theirs response but is it rational?

Thankyou everyone for their supportive responses it really means a lot and has rationalised my thoughts a lot more ❤️