I can't speak for everyone but my S.O.s mother killed herself (started the car in the garage and went to sleep). I avoid talking about suicide as much as possible. One time my car had an exhaust leak and I even avoided running my car with her around. I won't show her one of my favorite movies (office space) because of the one scene in it where the guy tries to kill himself by running his car in the garage. This is years after the fact, and she is well adjusted to it.

Your husband isn't just not walking on eggshells, he's being straight up insensitive. He knows exactly what he's saying and probably thinks it will desensitize you to it and make you get past things that trigger you. I'd be lying if I said I haven't thought the same, luckily I had thr tact to not do that. I highly recommend you see a therapist, even if you are handling it well and maybe even take him with you if the therapist will allow it. Talk to your husband about saying things like that and how you know he may be trying to toughen you up or desensitize you but that's just not how it works. He probably can't empathize with what you're feeling, and in the coming years you'll see that many people can't either. People will bring it up seemingly out of the blue and it will drag you back down to your worst point. They'll tell you their opinion on suicide unwarranted and they'll think they know your sisters character. I'm sorry for your loss, and I hope your husband wakes up to this. Suicide and mental illness is a real bitch.