Below is an excerpt from Why Giving Thanks to God is Important, from Got Questions.org. It' answers the question so eloquently I just had to share it with you.
"First Thessalonians 5:18 says, 'In
everything give thanks; for this is God’s will for you in Christ
Jesus.' We are to be thankful not only for the things we like, but
for the circumstances we don’t like. When we purposely thank God
for everything that He allows to come into our lives, we keep
bitterness at bay. We cannot be both thankful and bitter at the same
time. We do not thank Him for evil, but that He is sustaining us
through it (James 1:12). We don’t thank Him for harm He did not
cause, but we thank Him when He gives us the strength to endure it (2
Corinthians 12:9). We thank Him for His promise that “all things
will work together for the good, to those who love God and are called
according to His purpose” (Romans 8:28).
We can have thankful hearts toward God even when we do not feel thankful for the circumstance. We can grieve and still be thankful. We can hurt and still be thankful. We can be angry at sin and still be thankful toward God. That is what the Bible calls a “sacrifice of praise” (Hebrews 13:15). Giving thanks to God keeps our hearts in right relationship with Him and saves us from a host of harmful emotions and attitudes that will rob us of the peace God wants us to experience (Philippians 4:6–7)."
We can have thankful hearts toward God even when we do not feel thankful for the circumstance. We can grieve and still be thankful. We can hurt and still be thankful. We can be angry at sin and still be thankful toward God. That is what the Bible calls a “sacrifice of praise” (Hebrews 13:15). Giving thanks to God keeps our hearts in right relationship with Him and saves us from a host of harmful emotions and attitudes that will rob us of the peace God wants us to experience (Philippians 4:6–7)."
GotQuestions.org is a ministry of
dedicated and trained servants who have a desire to assist others in
their understanding of God, Scripture, salvation, and other spiritual
topics. We are Christian, Protestant, evangelical, theologically
conservative, and non-denominational. We view ourselves as a
para-church ministry, coming alongside the church to help people find
answers to their spiritually related questions.