Most Helpful Guy
First, I would do some research and confirm that Lyme's Disease could actually have been the cause of her behavior. If so, do you think she is being sincere? If so, you can forgive her. . . but forgiving is not the same as forgetting and you can't undo all that has transpired since then. You owe loyalty to your current girlfriend and resuming any kind of relationship with the ex-girlfriend will be threatening to the current girlfriend. Try to imagine that the roles are reversed and your current girlfriend is talking about resuming a friendship with a prior boyfriend. Not a good idea!