How to use grounding techniques when you can't feel grounded

I feel bad you are going through this causing you to be super stressed. But, when it comes to better managing your stress, the first thing I strongly recommend you to do “ BELLY BREATHING.”

What is Belly breathing? During “Belly breathing” you breathe in slowly and deeply, counting to 6 in your head, as your belly and lungs fill up with air. This means your belly stick out as you breathe in. Then, you let the air out, even slower when you breathe in, meaning count to 7 as you breathe out. At this time, your belly go back in as the air is slowly pushed out. If you are still not sure, you can indeed watch a video clip about it in youtube. Do this over and over until you feel relaxed.

Once you feel more relaxed, then now try to reframe your negative thoughts that causing you with lots of stress to a more positive thought that can help you feel joy, happiness, excitement, and so on. So, this is like changing from a cup half empty (negative) of water to a cup half full (positive) of water. Or better, changing the channel of the TV from something you do not like to watch to something you like to watch as everything has to do how you interpret your negative life event/situation that you are going through. We cannot change what has happened but we can change how we perceive and interpret it. Thus, changing your thought pattern to a more positive light from the negative ones could help you to better manage your stress caused by your negative life events.
Depending how resilient a person you are, it might take several training and disciplines before this actually happens or you can do this fast. Therefore, although different people face similar or the same negative life event, some people can cope with the situation better than the others.

According to the cognitive behavioral therapy, the thoughts, emotions, body reactions, behaviors are all interconnected to each other in response to a life event, whether positive or negative. This means that, when a person faces a positive life event, then the thoughts, emotions, and behaviors will be positive, and as a result this person will not have negative bodily reactions. However, when a person faces a negative life event, most people are inclined to have negative automatic thoughts, which will cause him to have lots of stress, and the more this person thinks or overthinks about this stressful life event the more he or she will have a strong negative emotion (stress, depression, anxiety, confusion), which in turn will cause the person to have negative bodily reactions such heart pounding, chest compressing, migraines, tiredness, lack of energy, and the list goes on and on. Then, this is associated with the negative behaviors such as difficulty sleeping, shutting down, eating junk food, and so on. 
These thoughts, emotions, and behaviors are interconnected to each other and how they work together to produce a certain type of emotion depends on what type of coping system, negative or positive, we are using. Thus, depending on the type of the coping system you are using, you could let the stress to come to you to the point that it resides in you and starts to control your life, or you can kick it out of your life when it comes to you so that it does not reside in you and it does not control your life. 

I hope this information has been helpful.