You haven't lost your faith.  What has happened, happens when we concentrate more on day to day living rather than our relationship with God.  We're so caught up in day to day living (and all the trials that go with it) that we neglect to spend a lot of quality time with our Heavenly Father.  We don't mean for this to happen; it just does.  And when it does happen, we're so empty inside.  Things are just not the same as they use to be; and we so want them to be.  Our heart actually aches for things to be as they were before.  So what has happened?

It could be that you are just not spending a lot of quality time with your Heavenly Father in prayer; and I mean a lot of time.  Quality time is not just shallow prayers (like God bless the world, bless this person or that person etc.)  Quality time is spending a lot of time with God in prayer; praying specifically for everyone and everything because we care about them and we enjoy being with our Heavenly Father.  Spend a lot of time with Him in prayer.  We should never cease praying as the Holy Spirit leads us to do so.  It is so important in our Christian walk.

Another thing that happens when we become overly concerned with day to day living rather than spending quality time with God is that we lose the joy of reading God's word, the Bible.  It becomes a chore rather than a joy.  When we read it, we can't even retain what we're reading and we can't even concentrate on what we're reading; most often, we just give up and set it aside.

When we find ourselves in a situation as above, we need to sit down and determine what's really important in our life and act accordingly.  If our relationship with God is more important than anything else, then we need to spend a lot time with Him - love Him and allow Him to love us.  We need to desire spending time with Him above all else - we do with others we love; then why not Him?  No one can love and care for us more than our Heavenly Father can; not even our earthly father - God is love.  He doesn't just possess love, He is love - true love flows from Him, and Him only.¹  He will never leave us nor forsake us - He will always be there for us.²

A lot of prayer, a lot of Bible study, a lot time spent with other Christians, and those who love and encourage us, is very important.  We need to determine to walk close to God and not allow anyone, or anything, to come between us and our Heavenly Father - and our walk with Him.

Look around at all that God has done for you and continues to do for you; thank Him from the bottom of your heart.  His grace is more than sufficient - it's everything.

Worship Him, and thank Him for everything.  In all that you do, do it as unto the Lord - your job, how you relate to others, and your Christian walk, should be out of your love for God; it should be your service unto Him.  Honor Him and others - treat others as you want to be treated by them and determine to walk upon the earth in true righteousness and holiness as Christ Jesus did (be Christ-like in all that you do.)  As much as possible, determine to live at peace with everyone, and do not practice sin (ask God to guard your heart.)  Quickly turn away from temptation, and do not consciously practice sin.  See others as God sees them.  And cast aside all that would hinder you from running the race in life that God has set before you.

Bible References:

¹ (1 John 4:8)

² (Hebrews 13:5)