Some good answers here already with much for you to contemplate.

I'd like to add some additional points for you to consider.

Consider your existing belief about, say, your financial situation to be like a battered old car.

How do I know that belief feels like that to you? Because otherwise you wouldn't be trying to get different manifestations to the ones that the belief is already giving you (e.g. trying to get an improved cash flow)...you want something more now that the current belief is not allowing you to have.

Your belief about something operates independently of how happy (or not) you are in the moment. It is the habitual thought pattern into which you have acclimatized regarding that subject.

As long as you drive a battered old car (your belief) slowly, it will probably keep you moving around. They won't be necessarily pleasant journeys (joyful manifestations) but at least you will get around.

Like most people who drive battered old cars, you just kind of get used to all the quirks with it. In fact, over time, you can grow to enjoy driving that old thing (you believe you are happy)...even though it is old and battered, you have got used to it and even other people can grow to accept that you are just that eccentric person who drives that battered, old car.

And, to be fair, the car may be serving you well at that slow speed. (happiness can still come about from the alignment of a small desire with a restrictive belief...the restrictive belief won't interfere much with a small desire)

Now assume that one day something happens in your life that causes you to want to drive that car faster. Maybe one day you see someone in a new sports car who drives really fast and seems to be having great fun (abundantly wealthy) and you decide you want to be like that.

So you start driving your battered old car more quickly to be like that person (you start focusing more deliberately on wealth).

So what happens when you start driving a battered old car like a brand new powerful sports car?

The chances are that you are going to keep losing control of it and end up crashing again and again...

...battered old cars just can't cope with those increased demands for speed and manoeuvrability (your existing belief about your financial situation contains too much resistance).

It's not your fault though.

When you are starting out in your driving career (start becoming more deliberate about focusing in your life), there's no real way for you to know just how fast you can drive your existing car (take action with an existing restricting belief in place) before you lose control of it and crash. That sort of thing comes with experience.

SIDE NOTE: Your emotions actually indicate to you whether your desire for what you want is in alignment (or not) with your belief about what you want but, remember, we are discussing a situation where you may be relatively new to "manifesting" and may not realize consciously yet just how much informational power exists in emotion

After a number of crashes, you just start to instinctively know when you are driving too fast (when your current belief is too restrictive) and, as a result, you sense that it's time to get a new car to drive at the new faster speed. (mold your belief more deliberately into a better place).

This crashing that happens when you first start driving faster (getting more deliberate) is quite common actually with many people and is nothing to feel bad about. It's just an indication that you've decided to drive faster.

Of course, people who drive slowly probably don't crash much - and even if they do, the speed is too slow to cause much damage.

So why not drive slowly instead?

That's simply because there is no satisfaction or thrill in slow driving. Look at the lack of passion, energy and focus in those slow drivers. You instinctively don't want to be like them...and they are only like that because they have forgotten they can drive fast because they have restricted themselves to those slow, old cars.

Driving fast is what everyone naturally wants to do! You were born to live life in the fast lane!

So just remember that crashing only indicates that you have a car that can't cope with the new speeds you wish to drive at. It's not that the universe is trying to stop you driving fast (it's just an indication of change happening, not a deliberate stripping you of your optimism), it's just that those crashes (manifestations) have now made you aware of the limitations of your current vehicle...something you may not have realized before when driving slowly...and that is very useful information to know.

Once you get used to driving a new faster car, you'll be zipping along and those crashes will seem like distant memories.

Regarding the other point about things happening when you finally give up...what is it that you are really giving up?

If you think about it, you'll realize you are not giving up on your desire (because you can never un-launch a desire), you are only giving up on your resistance to your desire.

So you are, in fact - by giving up - putting yourself into an excellent place to receive your desire!

It's paradoxical, I know, but these subjects are full of apparent paradoxes and, often, at the point of paradox is your greatest power...it's the point of perfect balance...like a tightrope walker who is hovering between falling one way and the other.

The most efficient way to manifest what you want is to desire it strongly and then give up on it ever coming.

But you can't fake the giving up bit.

The complete manifesting process always involves dealing with the apparent opposites of focus and release at some point.

That's why it can be useful sometimes to make yourself think you are assigning the task to something or someone else (like "the Universe", "God" or a manifesting box) so that it helps you get into the feeling of giving up. i.e. releasing your resistance to what you want.

Hope all this gives you a few further insights into your situation.