Let me offer my condolences. I hope you will find peace in knowing you did all you could do. Your husband knew he mattered and was loved. That is what we all want in this world. You matter too. I have been in a grief support group which I highly recommend. Sharing is the best way to find steady ground again. Clearly, your husband loved you and wanted to give you a break, so he would want you to go forward with your life. Take some time to regroup, but then start saying "yes" to things you never thought you'd enjoy. It is OK to have fun again; find what makes you happy and do it. You can do this. Women can do hard things.
A big hug to you.