In the original Greek canon, because Artemis helped birth her twin right after she was born (fully grown btw and same with Apollo) she was horrified and never wanted children. So she swore of men. However, she does fall in love with Orian but she accidentally kills him b/c Apollo tricks her and she mourns his death. So, she can love but choses not to because she fears the pain of childbirth (b/c back then there was no contraceptive sans chastity).
Orion was a very skilled hunter and was occasionally a hunting companion of Artemis. She fell in love with him but kept quiet about it. Apollo figured it out and tricked her into killing him (his motive was unclear and it depends which myth you read).
I very much hate how so many paint Artemis as a "man hater". There is a difference between having no wish to be with them sexually or romantically but still respecting them as human beings and another to hate men just because of their sex. :/