Does anyone here struggle with tasks and daily activites as well?

All the time. The lack of motivation and some other things has my psych thinking I might have inattentive ADHD, which is more prevalent in people with autism. I found that after I did some reading about inattentive ADHD that I'm ticking alot of boxes.

Found a good, informative lecture on the topic.

Yep, unless it's something I find interesting, but even then it also depends how much I have left in my battery for the day. The more I don't want to do it, the more juice it's going to drain from my battery.

Fortunately, this is something I solved by establishing a set of routines which I do not deviate from. Each day is a repeat with minor variations depending on the day of the week. This helps me keep my place spotless, eliminates any mental energy put towards figuring out what to eat, and makes things like shopping less stressful as I just place the same pickup order each week. The BIG struggle for me is when I make the effort to change my routine for people (friends) to accommodate plans and they cancel on me or try to change them last second. I don't think they will ever understand how much energy it takes for me to change my day and mindset for them.

sometimes i have no energy left after a day of overstimulation.

Yes.

When I have something i'm thinking about or want to work on, other things - including stuff like feeding myself properly (as I have to cook at least somewhat for economic reasons) - are interruptions and very frustrating. I like my drive to do things I care about and have special interest in but it can lead to self neglect :p

If I didn't have such a large appetite, or got something affordable i could prepare and eat that was actually nutritious and filling in a couple minutes, it would be much less annoying ^..

Its not just making food, but that's a major one.