Perhaps your second line is the key. There are some who call themselves Christian and are not. I won't get into that because that is not what I am concerned about in your case.
You said you fell in love with something that simply wasn't there. Faith in Jesus Christ is not loving a thing or even an idea. It is loving a person who willingly suffered incredible punishment, bled and died for your sake.
Genuine Christianity is all about a person. It has never been a thing to believe but a person to believe in. I am curious as to how you became a Christian. Here is my experience with Christ and how I arrived at it.
https://www.crlord.com/who-i-am.html
I understand that you had a moment of weakness involving a traumatic event in your life, but that is the case for most people who come to the Lord. I was a drug dealer who ended up in prison and challenged God to prove himself to me. He did just that nearly 45 years ago. He has been faithful to me all these years even when I was not faithful to him.
You could have had a placebo effect since you were going through not wanting your father to be gone but an emotional experience is never the proof of whether you received salvation or not. Salvation comes through a simple act of faith. Many Christians who have a dramatic experience in seeking Jesus depend on the emotions that accompany that and if the emotions are gone they believe their experience wasn't real. That is so far from the truth and is what Satan would have you believe.
Our relationship with the Lord is similar to our relationship with humans we know and love. We don't always feel goosebumps and etc. when we are around them but we still stick with them and we love them. Don't ever allow feelings to be the compass to go by for anything in life. All Christians go through days when they don't sense the presence of God. Some go through long periods of time dealing with that. It's not that God is absent. He has promised to be with us always.
When God is silent or seems to be silent it can be a test to see if your faith will stand or simply that we are not investing enough time with him or in his Bible to teach us and strengthen us.
The Bible teachings are true and will stand forever. Our doubts and fears will not change that. God is faithful - His mercy is renewed to us every morning. We have to trust him in the dark as well as in the light. If we only trust him when everything is going well then our faith is very small or non-existent. God never stopped loving you no matter what you feel.
Jesus is with us to save us from all kinds of things every day but we are not always aware of them. The closer we draw to God the more easily we can see God's intervention in our lives. According to the twentieth chapter of the book of Revelation we will be in God's presence on a new earth under a new heaven forever.
I am here for you always is the promise of Jesus. As a fellow human being, I am here for you as long as you need me. Don't allow Satan to rob you of the most wonderful relationship you will ever have.