Feeling miserable

This is honestly how I feel. I lack motivation to do anything for myself. It’s all for others. These feelings have became stronger after my brother passed away this April. We weren’t so close but we just had each other after our parents had passed away. Now the family I was born into has gone.
My brother left behind his wife and 2 young daughters. I feel mentally and physically drained from life. There was a lot to do after he passed away.
I am married with young kids. Recently I’m more anxious than usual and I feel like I’ve had some bad luck which doesn’t help such as a car accident.
I keep thinking I have no one who will look out for me (e.g. if my husband is ill, his parents will keep calling him asking how he is, he can go to sleep early. Whereas I don’t get anyone asking about me and neither do I get to go to sleep early lol).

I also don’t see the point in anything. I just think I’m going to die anyway.

I don’t know if anyone has any advice on how to remain positive. I don’t show anyone how I feel and do get on with life. But truthfully I know people have it harder. I just wished I could be happier, less anxious, positive and less annoyed with everything. I’m quite unlucky and I’m trying to accept this.