It's really hard for me and doesn't come naturally -- as I am a regret and second guess type of person. But in your situation, hold on to what you have that others don't. As you say -- you are in your 30s, not someone who was "downsized" in their 50s or 60s. Also, you have a degree and experience from your last job; whether you use them or not, you have them and not everyone does. Just try to trust that everything will work out for you exactly as it's supposed to.

Agree with the PPs who said -- don't listen to the naysayers. They are typically demonstrating their own insecurities by making everyone else feel bad about themselves.

Agree with the above posters....
With the death of my parents, baby nephew and grandparents all in two years, I stopped feeling regret, and starting feeling immense gratitude. In almost everything.
(As a result, quit my unsatisfying job and found a better one. That also helped.)

In terms of how you will move forward -- one step at a time. It can be baby steps of fixing up a resume, or talking to one person in your network, or whatever -- and from there you will gain momentum. It does not have to be an all out blitz on the first day.

As for not dwelling -- it's hard. Realize that you don't know what will happen BUT neither do the naysayers. I am assuming there are naysayers who are telling you -- your last job was the best you ever had. You don't know that and they don't know that; it is always possible that there is something equivalent or better out there -- you and they don't know it yet because you haven't found it yet.

Things have been so bad in my life that I've learned to just keep moving forward. I can't change past decisions or events and there is no point in dwelling.

Stop waiting for opportunists to recognize your value and become an opportunist.

Silly advice. No one cares more about you than you. Go get 'em!

Ignore the naysayers and push ahead.

If you watched Mad Men, be more Don and less Pete.

Just realize that life is moving forward and you have to keep moving ahead because time will not wait for you. And that negative thinking gets you nowhere.

Until I had suffered, I wasn't able to fully appreciate what I had.

Think of getting the flu, and how just getting from the kitchen to your bed leaves you rasping for breath, and then you get better, and the first day you run up a flight of stairs without arriving panting. That, but on a larger level, and in all aspects of life.

I'm one of those people who regrets practically every (career) decision I've made and at the same time don't get how I'm going to be able to make some much needed changes. I am sitting here thinking -- wow, that job that I killed myself for but never got any credit for was the best thing that ever happened to me -- and I don't even want to try to move forward. But realistically I know that's dumb -- I'm well educated; in my 30s -- not my 60s; I have a few people who do believe in me etc -- I should at least want to try.

How do you get yourself to a place where you're thankful for what you have and grateful for the moment/hopeful for the future? I have always been a look back and regret kind of person.