I feel for you right now, as I am going through a similar situation with the loss of a dog 4 weeks ago.
I have been stable for a long time, but now friends and family keep telling me that it's just a part of life and to just try to get over it. I explain that my change in mood for the past weeks isn't easily coped with (they all know I have bipolar disorder). They wonder why someone with bipolar disorder just doesn’t try harder. They think that if they exert more effort, they’d have the life they want. They wonder why everyone else who experiences mood swings can cope with them but someone with this disorder can’t.
But this implies that bipolar is a choice. Would you ever say that to someone with diabetes or leukemia? Doubtful....