Om Swami
How can I stay thankful to God even when I didn't get what I wanted or lost something?
Remember what God has given
Real bhakti (devotion) is feeling complete even when God took what you liked or did not give what you needed. There is much that He has given, and you would learn its value if it were taken from you.
Bhakti is that in which you feel complete, thinking: it is alright that You took from me what I liked, and alright that You did not give me what I wanted.