In Wide Sargasso Sea, Rhys often depicts love as a drug-like trance. The love we see between characters in Wide Sargasso Sea doesn't seem romantic; it seems like an unhealthy addiction. Antoinette displays a lot of "love" for Mr. Rochester, so much so that she feels the need to give him a potion in order to have him reciprocate her "love". Antoinette's idea of giving Mr. Rochester a potion to make him love her again shows her desperation for love. It's like she's going through a drug withdrawal, except with love instead of drugs.
Drug withdrawal can be very traumatic, and we can see that from how Antoinette behaves. The more addicted one is to a drug, the more difficult his/her withdrawal from that drug is for him/her. It's obvious that Antoinette is very consumed by her love for Rochester, especially when she says "Say die and I will die. You don't believe me? Then try, try, say die and watch me die." To most audiences, this is not at all a romantic thing to say. But after Antoinette says that she would die if he told her to, Rochester and Antoinette proceed to have sex. Antoinette's addiction is considered to be love.
Antoinette's withdrawal is just as extreme as her addiction, though. When she first comes to Christophine to solve her problems with Mr. Rochester, it appears that she just wants to have a conversation with Christophine about the matter. But she actually intends to obtain a potion from Christophine to make Mr. Rochester love her, even after Christophine told her she should leave him. Antoinette talks to Christophine about how afraid she is, but she doesn't know why she's afraid. She's likely afraid of the prospect of losing Rochester and his love. Despite Christophine's advice, Antoinette insists on giving Rochester the potion. She wants to end her withdrawal and continue using her drug (love). And she's willing to go to extreme and risky measures to do so.
