For years I behaved as though the companies I worked for had my best interest at heart. Having been in IT for 15 years now as a software engineer I can tell you that if you could do a personality profile on an organisation, most would turn out to be sociopaths. You need to change your attitude and behaviour towards your organisation or it will eat you up and when they've finally made you lame they will spit you out. There's only one person that's on your side , and that's you. This means that you have to put your own needs ahead of the needs of your organisation, the organisation can and will look after itself and at great cost to you if you let it. You really have to learn to fight your own corner. Those clock watching consultants are not something to be criticised, they've learned the lesson, they're looking after number 1 because they've learned that no one else will.
With regards delegating. It really is short term pain for a long term gain. It also allows you to move up or sideways when the opportunity arises, as you're not totally irreplacable in your current role. I know that sounds like you're possibly working yourself out of a your own job but so what, it sounds like your current role as it stands isn't something healthy for you to stay in.
I always like to keep in mind that when it comes to dealing with people and organisations, "They will treat you as you let them". It places the responsibility for how you are treated in your own hands. Couple this with taking a broader view of your market value by putting your CV out there and talking to agents about other opportunities. This will allow you to see your full breadth of options including those outside of your current company so when it comes to you saying no you wont fear the potential consequences so much. You'll be decoupling yourself from the implied power your company has over you which is "do what we want or we get rid of you" and in so doing you neutralise their trump card.
I hope you don't take this too personally. I've seen this anti pattern time and time again and have been there myself, burned out a few times, wondered if I still love what I do and I've come out of the other end charred and smoking but a little wiser......perhaps.
Best of luck
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