I'm so sorry to hear what you're going through. It's so easy to go through life thinking we have it all and can find happiness and it is never going to change - then suddenly it does and you feel like you've had the entire ground just yanked out from beneath your feet. To lose the two people most important to you... I can't even imagine. I hope you're doing okay. I hope you're acknowledging that it is normal for you to be devastated now and that it will most likely continue for a good long while. If you weren't feeling this way, that's when something would be wrong! My hope for you is that you've got a really good, strong supportive team, even if the "team" is just one or two good friends or family members. You need someone you can talk to, vent to, cry to, whatever, at least until you're starting to feel more able to get back to a new "normal". If you ever want to chat, please let me know - I'm here for you and I'm sure a lot of others will be too. Keep posting if you need to. Hope it helps and I hope you're hanging in there.
Everyone grieves in their own way and at their own pace. You've suffered such a loss. This one is going to take time. When my Mom died, it wasn't too hard for my Dad because she'd been sick for a long time and we all believed she was probably better off not suffering anymore. When his second wife died suddenly, it was much harder. When we talked he used to say, I just eat to live. It took time, and only time, and then he met someone else and married a third time. When he died, she was widowed for a second time, and for her too only time helped. She is now married for the third time. You have to do what feels right for you. If that's a vacation, take one. If that's not a vacation but it's throwing yourself into work for now, do that. If it's just time spend in familiar places with friends and family, do that. But grief isn't a mental illness, it's a condition of life for everyone but sociopaths. Some people get over things much more easily than others do. The only constant here is, do move on at some point. Don't stay mired in grief forever. It will then become a mental illness. As for blame, there isn't any. Every day is a risk for everyone at all times. Sometimes the risks are known, as in your case, and sometimes they are things we don't think about until they affect us, such as war and natural disasters or just falling off a ladder. Nobody gets out of here alive. I personally find the tone of your post very positive -- you are moving. I'm guessing you are a survivor and will find your way forward, but I doubt you will ever or should ever completely lose some piece of yourself to this sorrow. Grief is part of how most of us learn how to have empathy for others and to try not to hurt other people. Those who move on too easily usually are toxic people. People who never move on never move on. You will set your own pace. My only advice is, at some point, fall in love again for all the positive things it gave you. When you're ready. Peace.