Unless you solve a specific problem that is worth a lot of money to businesses, the intrinsic value of your software is probably much smaller than you think. Most of the value in most software businesses comes from development, design, optimisation, sales, marketing and so on. In particular, selling software to large companies is a slow, expensive process that has little if anything to do with the quality of your software. You mention AI and NLP in the comments, which makes me slightly nauseous as regards the actual commercial prospects of your software - such projects tend to be academically impressive but monstrously expensive and near-impossible to market. Obviously I'm purely speculating, but I'd suggest getting your product out of academia as quickly as you can and talk to your potential customers. It's very easy to waste years of your life and a pile of VC money on a brilliant product that nobody wants. If you haven't read Steve Blank's "Four Steps to the Epiphany", stop reading this and go buy a copy now.

Open sourcing a project has many potential benefits. It looks excellent on your CV and is usually the best way of getting hired by someone you'd actually want to work for, as it proves that you can actually program. If your software becomes widely used, there are excellent opportunities for consulting, writing proprietary add-ons, books, speaking engagements and so on.

You say "i don't want some big company coming and taking my source and putting it into their product even if they do credit me". In fact, that's exactly what you want, because overnight you become the world's leading expert on a product by a big company, with everything that entails. GPL it and they can't distribute the software without also distributing the source. They can use the software internally of course, but guess who they're going to want to hire if it becomes mission-critical? That's the basic reason to open source a piece of software - it opens the possibility for other people to develop, market and become reliant upon software you wrote.

If you're willing to bet every penny you have and every minute of your life for the next ten years, then make a business of it as a proprietary product. You've got a great deal to lose, but you could end up richer than Croesus. If you open source it, all sorts of opportunities may open up for you with very little effort on your part.