I don't want to let go of attachments because I don't trust that everything will be okay unless I am in control.
Holy Spirit is asking us to be set free (!) of the need to have outcomes be controlled, or follow what we think is in our best interests. We want to be in the drivers seat with our ego, directing things and enforcing things, trying to resist what IS and instead enforce what we THINK things should be.
This is all about ego control and manipulation. I want to control so that I can seem to 'make happen' a particular situation. I don't trust that things will be okay unless I don't do this. I do this because I've become convinced that I NEED the situation to be this way. I think I have this need because I've got some kind of funky ego belief telling me that if things AREN'T this way then I will not be happy, or getting what I want or need. ie I'm going to lose or have lack or have something taken away if I don't make things be a certain way.
So this really boils down to fear, not feeling safe, and the belief that we need to put up defenses against what's happening in order to protect ourselves from attack. The trouble is that these very mechanisms, which are mechanisms of control and resistance, are the very things which CREATE a belief in attack because they ARE an attack.
Each time you create an expectation, or invest into attaining a particular outcome, you are setting yourself up for failure. There's a good chance events are not going to go the way you expect them to, and when that happens you will react unhappily. There is also a chance things will go the way you want, which is the ego's carrot on a stick, and then you think you have somehow 'won' the prize of getting away with murder. But its a gamble that you will likely at some point lose.
These investments into NEEDING things to be a certain way, to fulfill some kind of strange belief that 'then I will be happy' or 'I can't be happy when things aren't the way I want them to be', 'attach' us to these outcomes. We're pinning our hopes on them. We're depending on them. We're relying on things going the way we want and build up all this fear and anticipation about it turning out.
This 'attaches' our mind to these outcomes because if we DEPEND on these outcomes/events/people for happiness then we're HOLDING ONTO the ego's false promise or fantasy that GETTING this outcome will bring you salvation. Salvation will free you from whatever supposed 'need' you think you have and deliver you from the 'suffering' that you think you will experience, or maybe even do experience, when outcomes aren't the way you want them to be.
So really this is all about looking for salvation in the wrong place. Putting our faith into being CAUSED to be happy when certain things happen or certain events line up in a certain way. We're depending on EXTERNAL stuff to change what our experience is, and are relying on someone or something else to happen TO us to indirectly CHANGE us into the desirable state we're trying to achieve. This indirectness is passive and is also the role of the victim, in which you are sometimes at risk of attack and sometimes at risk of reward, and are gambling that if you steer things toward reward then you can avoid attack. But both are depending on the ego and both depend on external, separate things, to come along and affect you in a preferable way.
You can only be affected by things if you are not being responsible for yourself. You can only be changed by external things if you are not being who you really are. You can only have your happiness affected positively or negatively by outside influences if you are not aware that Joy is within you and comes from God and can never be removed. And you will only seek and not find salvation in these external outcomes if you are not finding contentment and needlessness within yourself. You will keep seeking (attaching to/depending upon) and not finding (losing/suffering) while you believe that you have a real need that is unfulfilled and that needs to or can be fulfilled (finding salvation) by some external, separate source beyond your control. And so then your attempt to control is an attempt to control what is beyond your control, to try to coerce it into becoming what you want (your savior).
So it really all comes back to whether you believe that you don't have God. Or that you are not as God created you. Or that you're lacking or failing in some way or have an absence of sustenance from God. If you're `in need` then you will seek and you will project and you will seek for false idols and you will attach yourself and become DEPENDENT UPON external stuff. This dependency is a form of slavery and is a form of losing yourself or 'transferring' yourself into the external thing. And this BINDS you to the ego's `level 1` world of duality and suffering. It binds you to the physical form and it binds you to a separate existence. All of your external dependencies and false needs keep you weighed down in the quagmire of darkness in the ego's world, and prevent you from staying squarely in the Holy Spirit.
So we need to let go of mentally and emotionally depending on anything other than God, essentially. Depending on God means looking to God for fulfillment and happiness and meeting all needs and TRUSTING that you will be taken care of if you let go of trying to care of everything yourself. But it does involve a surrender. You have to let go of your tight grip of fear that says... I won't fully let go because if I do, shit is going to happen that I don't want... which really means, shit will happen that does not align with your ego's plans for what IT thinks will bring you salvation, which is GROSSLY MISTAKEN and actually leading you into suffering. Holy Spirit's plan is better ;-)
So it's really about learning to trust Holy Spirit, to develop a trust that you CAN and should let go and allow and accept in order to RECEIVE LOVE and SUPPORT and HOLY HELP, and that it is SAFE to do so, and that it does not mean horrible suffering will follow. Going from fearfully holding on to surrendering and letting go takes a bit of a leap of faith. But once you've taken it, you'll let God be on your side. And you have mighty companions.