<human>: Can you succinctly summarize the text in 1-3 sentences?

So he divorced my mother after having an affair with someone half his age, and from 12 years old until 22 I would only see him every other weekend, and he would put in minimal effort to be present for big events in my life.

Since dating his current fiancee, he has been more involved with my life and honestly he may be trying to make up for those years. Needless to say I was not thrilled when he asked me to be the best man, and even less so when he specifically asked to give a speech at the reception of about 40 people. I have no fear of public speaking, and I can talk about things I am passionate about. But that's just it, I have no inspiration to write a speech about a man who has been such a source of conflict in my life. So I guess I'm here to ask for some advice on what I could say. I am happy that he found love again, he will be a step father of two children and is very involved in their lives (taking them on trips, encouracing after school activities,etc)
So what I ask of you reddit, is some advice to on some filler material since all I can come up with is that I am happy for his new marriage. He already said it doesnt have to be too long, but all I can come up with is a short paragraph.
<bot>: Have to write a best man speech for my once distant father and falling short. Any advice on how I can pad it to make it longer?