Suddenly become aggressive ?

I have two mini lops, my buck Humphrey is 9 months old and my Doe Olive is 7 months old. Humphrey was neutered a while ago, and until Olive was spayed we kept them in separate cages, but got them out at the same time occasionally to bond, (making sure he didn’t mount her). They were getting on really well. The other day I took Olive to be spayed, bought her home and he didn’t really react differently. But then she went into GI Stasis and I had to take her back, she was kept in the vets for 36 hours being monitored. I bought her back yesterday and Humphrey has been none stop attacking her cage, trying to get at her, being so aggressive. This morning he bit me, which has never happened, and he went for me twice. I don’t know what’s going on, is this normal? Is it jealousy or have they lost their bond ? I’m scared to even go near him please help.
Thanks
Lydia