Like a lot of developers, I find it hard to do marketing and sales for my projects. I've let side projects die without even sharing one link on a public forum. Here are my tips that's helping me emotionally strong to keep going.
I used to think the key to selling is to give extra, but there's a catch. If you are liking or following someone just because you want them to buy your product and they don't buy it - you're going to be less motivated to give next time.
When you give away value for free WITHOUT EXPECTATIONS, it always surprises you in a good way.
How you see others is going to reflect back on your little brain before you send a dm, or post a link. Don't be too harsh on others selling to you.
Beyond the product, beyond your $$$ who are you? I often link my self worth with my work. It helps me do what I love. However if you take the losses of your product too personally, you're going to quit before you make it better.