It's entirely possible that there is something else going on.
Perhaps the boyfriend has started seeing someone else or wants to start seeing someone else but wants the OP to break up with him and is using the snakes as an excuse to cause that to happen.
The thing about speculating is, you're just guessing.
A lot of people with a lot of experience with this exact scenario have given her advice and some with almost no experience with this exact scenario have piped up too.
Whatever she does is for her to decide and her friends and hopefully family, to support.