Hello, and welcome.
I'm very sorry for your loss.
It's a shame that at a time of loss and sadness, there has to be such dissension within the family.
The first row is typically reserved for family, but who sits closest to the casket doesn't really matter. Both you and your mother in law should have sat in the first row, preferably closest to the aisle (nearest the casket?) and your daughter and his brothers (if they attended) should also have sat in the first row on either side of the aisle or in the second row, behind you, if there wasn't enough room for all closest family members.
Your daughter should have discussed the music selection with you, in advance, out of respect for you and her dad.
Your only child and his family have not behaved appropriately, in not speaking to you for over 7 years.
You don't mention if this was a current husband or ex husband, because that would make a difference, but if he was your current husband at the time of his demise, you should have made all the arrangements, with the help of your daughter and those closest to him, like his mother and brothers.
From your description, these people did not treat you well, and were very rude to you. I understand why the sitting arrangement upset you so, and you're right. You should have been sitting in the second position, right next to his mother, not in the fifth position.
I'm sorry this happened at all and hope you can get over the upset by just reminding yourself that they were rude and are selfish people. I'm sure you have more important people in your life that check in with you and care about you/love you very much! Considering the amount of time that has gone by, put it in the past, let it go and don't waste time still being mad over this, now. They were at fault, not you, and there is a saying, "what goes around, comes around."
I hope this helped.
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