So, you think you might be getting benched. When you feel like you might be getting benched is the perfect time to find out if you're actually getting benched. Of course, no manager will ever tell you that straight-up, because they want to retain you for as long as possible (mostly to give them time to find your replacement), so you can't ask them straight-up, they'll always say "no".
Here's my standard answer to anyone who thinks they might be getting benched:
Step 1: Talk to your manager and raise your concerns. You can say straight up "I think you might be benching me" if you like; I would probably do that myself. Take the issue head-on and explain exactly what you're feeling and why. Tell your manager this is a problem for you and you want to know how you can work together to resolve it (of course, your manager benching you is their problem not yours, but you want to at least pretend to be accommodating, even if you don't feel that way).
Step 2: Listen to your manager's feedback, and listen carefully. Your manager will probably say something like "we have some more projects coming, they're being finalized, give me some time and I'll get you something". If your manager doesn't promise you a project, that gives you an opening to walk out and, as stated above, your manager wants to retain you, at least until they can find your replacement. If you are in fact benched, this will be a lie; if you are not in fact benched then this will be the truth.
Step 3: Find out whether or not your manager is lying. This is much simpler than it sounds. Ask your manager for a hard deadline on when they expect your next project to be ready for you to start working on it. If they give you a wishy-washy answer like "well, I don't know, it's going through the pipeline, blah blah blah", that's a lie. Otherwise, they'll give you a straight-up answer, and it will likely be sooner rather than later (within a few weeks). If the answer is more than 2 weeks away, I would treat that as a lie as well, because 2 weeks is about as long as it takes to find your replacement if they're already in the pipeline. Otherwise, the answer is within 2 weeks from now.
All of the above should happen in 1 meeting, no back-and-forth emails or multiple chats or whatever. Schedule a meeting, get this resolved.
Step 4: Polish your resume and start sending it out. Don't wait for your manager to come back with the project. The sooner you start applying, the less time you'll have to wait to find a new job. You can always withdraw from applications if your situation improves, so, just in case your manager is lying, start sending out resumes anyway. This is regardless of whether or not you believe your manager is lying; even if they've given you a deadline within 2 weeks, still start doing this. In fact, start doing this especially if they've given you a deadline within 2 weeks for your next project, for reasons below.
Step 5: Wait out the appropriate time that your manager has asked. If they said a week, wait a week. If they said 10 days, wait 10 days. Do not wait a single second longer than you were asked to. If, after that period of time, you have your new project, then great, you solved your problem and you're not being benched! However, if, after that period of time, you're still without a project, have another meeting with your manager and ask for "an update on the project". The goal of this meeting, for you, is not actually to get an update on the project; at this point, your manager missed their deadline, and that should be good enough to determine that they lied in the previous meeting. At this point you should already be prepared to leave the company (and you should have already applied and started interviewing elsewhere, as above). The goal here is merely to see what your manager has to say; personally I'm always a fan of giving the other person as much benefit of the doubt as I can and hearing them out if they want to tell me something. Probably they will give some excuse and extend their deadline. If they extend their deadline beyond end-of-day, that's a clear lie. Otherwise, give them until the end of the day and see what happens.
Step 6: You can at this point continue grilling your manager over why the project is delayed, why you feel disrespected, and so on, if you feel like it; you should already be prepared to leave the company so it doesn't matter to you, if you want to let your manager know how you feel. You can also simply drop the subject and continue your applications and interviews elsewhere and not worry about it. But either way, if you made it here, you are 100% being benched and should act accordingly. Functionally speaking, even if you're not fired per se, you are fired de-facto and you should act as such. You need to find another job ASAP, which is why you should have already started applying back in step 4 and you should already be a week or 2 into your job search at this point and have a few interviews lined up.
As for the rest of your question, it sounds like you just got a crappy position. This isn't what the software world is like, it's normally very collaborative. Find another job at another company and you'll be much happier, don't give up!