Images show as broken but they are not

This kind of thing used to happen to me all the time when working on HTML emails and one-off pages that weren't part of a Defined Site.

Do you have your site defined and have that site selected in your Files window dropdown menu?

If not, even for simple html emails, DW handles your assets better inside a defined site.

If the image does not exist at images/myimage.jpg that could be a cause of the issue. Are you sure the path is correct?

Also, when you say you are using Save for Web, are you using a CC version of Photoshop with the legacy save for web feature, or are you using an older version of Photoshop? Also, is it happening with all images or only select images? And what happens if you switch to live view? Does the image then appear?

The code looks just like it should, just like other images, and I use Design View.
<p><img src="images/myimage.jpg" alt="blabla"/></p>

The problem seems to occur mostly when I save new images (I save an image for web in Photoshop in my images folder, go to DW, insert the new image, and voila - I get this broken image. Uploading the page it is ok though on the web.

What does your code look like that causes this issue in live view?