Triggers and substitutes.
Figure out what you're doing/experiencing/feeling/thinking right before you find yourself on eBay. Where are you? What time is it? What device are you using?
Now think of something or a few things you'll do instead of EBay at the trigger moments. Other site, other activity, other distraction.
We're not so good at subtracting behaviors, better at substituting. Like when the dog has something she shouldn't. Instead of yelling No we say Trade! And offer her a toy, treat, or other acceptable "shiny object".
Now when you notice your trigger, or find yourself back on the site, you can say Trade! and go for the substitute.
Also helps to do a letting-go action. Like, empty the watch list and turn off stalking notifications. Possibly set yourself your clear terms. No more eBay for the year? 30 days? Ever? Also these other good ideas, like deleting bookmarks, cookies, apps, etc. that make shopping--er, I mean just browsing---so easy and mindless.
If you're a gold star kind of person you can track your days of freedom-from-eBay however you like. If you're a rewards person you can toast yourself with the latte at the bookstore or at sunset at your favorite park or whatever.
You have to do this your way, and to know why you're personally doing this, too. More than to avoid the negative effects, you need to feel the positive reasons too. Only you know what they are. Feeling in charge of a well-curated life? Being a person of higher standards (whatever that means to you)? Glowing over the accumulating stack of $$ you're setting aside for that thing/experience you really really want? Whatever it is, you'll have that to feel instead of the boost then crash, or whatever, feeling from buying. Feeling the feelings is why we do what we do, after all, no matter how logically minded we are. She says from experience.
You can do this. Good luck.
