There are a few things that come to mind. The first, and the easiest, is to light a candle with the intention of sending energy to that friend. This can be done through simple visualization techniques. I actually wrote a post about it → The Art of Healing - Sending Energy to Others
You could also either walk them through a spell on their own or do one for them. Here are a few examples of spells that are on the Spells8 site 
‘Uncrossing’ means getting rid of all unwanted and unneeded energies and attachments.
If you believe you may be suffering from a hex-related illness or a run of misfortune, try an uncrossing ritual.
Are you going through times of fear or uncertainty? If you’re craving peace of mind for at least 5 minutes, try casting this spell for inner peace and harmony. Never forget that you are a being of potential, of peace, of love, of power . The light within you can never be extinguished.
Both of these can be adapted for your friend’s situation 
I also recommend doing a freezer spell if you don’t mind binding someone. I talk about that in a nother post as well → Magickal Binding