Firstly, I am sorry that you are going through this tough phase in life. I am also currently going through the same so, just some suggestions from my experience & what I am doing to deal with it right now:
Immediate Actions:
1. Work/Distraction: I was at a point where I felt like I should take a break from work because I wouldn't be able to handle the stress at work in addition to the stress on personal front. But my friends & family suggested I continue working. I did that & I realize that suggestion was bang on, It provided me a distraction for at least 8-9 hours a day, which I would have otherwise probably spent crying. It also did not bring me to a phase where I woke up in the morning looking for a purpose/reason to get up. I had to get up & start working.
2. Routine: I developed a routine for myself by incorporating at least 1 hour of exercise & working towards better fitness which had been my goal for a long time. As a part of the routing, I also started focusing on eating healthy, Sure enough, I started seeing results on the weighing scale & measuring tape. It gave me some sense of pride & achievement, which is a so valuable at a time like this.
Mid-term actions:
3. Pursue hobbies/interests: I have recently started feeling like I am accepting this huge change in my life a lot better than I was a couple of months ago. With that I decided to start pursuing hobbies & interests that I had lost over the last few years. Without a spouse on the picture, I realized I had a lot of free time on hand. So I decided to restart my vocals/singing training.
4. Doing things that make you happy, even if there is no reason to do them: I love make up, skin care etc. I love trying on different make up looks, nail looks. I started doing more of this, even if I had nowhere to go. Just doing something that I like doing without any agenda except to make myself happy... That gave me more pleasure than I imagined it would.

These are the things that I have done over the last 3-4 months. This is a journey & I might have some new suggestions a few months down the line as I walk this path... I will be sure to share an update whenever that happens.

Sending all the love & prayers your way to deal with this.

Love,
SushiNCorn