I wanted the divorce and felt so guilty that I signed the agreement that was not fair at all. Now I am struggling hard financially and he is living in the lap of luxury, not working, traveling etc. It's really not a good situation.... I'm wondering if divorced couples ever go back and renegotiate if o e of them is not making it.

Not to my knowledge-unless one of the parties deliberately misled the court by providing untrue or misleading statements/financial information.

If you've willingly signed the settlement papers (ie Not under duress/did not lack mental capacity at the time), it seems doubtful that you could 'go back' and ask the court to reconsider the settlement amount or terms.

I read recently: Marriage is about love, divorce is about finances and unfortunately, the financial 'boat' may have now sailed...

The laws where I live may vary from where you live however, so is it possible for you to book a short (free?) consult with a women's support service (maybe one where lawyers volunteer some free consultation time) to check where you legally stand?