Unfortunately, I have some experience with this topic, although a decade ago. Much like parenthood, you'll find everyone has very well meaning, yet typically useless advice, so don't take it personally when they won't leave you alone or they sound out of touch. And, here's my contribution in the genre:

"There was just the same distinct sensation where nobody has any idea what I feel like"

Oh, I bet your family has a glimmer of an idea. Spending time with them, just doing "stuff" with them, even just talking or emailing, will help. The funeral-industrial complex is heavily monetized and optimized for massive profit simulation of what you actually need. So don't expect that wearing a suit for two hours while paying multiple kilobucks will have much effect, or worry if it doesn't. Then again, however pitiful it is of a simulation of whats needed, funeral rituals do at least imply the right track, "increased familial interaction" for awhile seems to help quite a bit. TLDR the funeral will be a waste of time and money, yet it is none the less sorta pointing in the correct direction, so whatever you normally do with your family, do more of it for a bit, you'll feel better.

Also its your head, don't let people tell you what it should be thinking, as long as its not hurting you. So don't sweat not following the grieving steps in the precise order for the correct amount of time at what they claim is the correct intensity. Whatever path you take, you'll get there your own right way eventually.