he thinks that catholics commit sin for praying to someone who is not God.
Protestants have a different idea as to what prayer means than Catholics.
One form of prayer is worship, in that sense we only worship God (the Father, Son or Holy Spirit)
Prayer in the sense of asking for something is also very common. Catholics believe that Holy Mary and the Saints are in heaven with God. The idea is that they can help our cause.
A (poor) analogy would be if you are a guilty of some crime and are looking for a presidential pardon. Imagine what kind of clout you would have if you knew the President’s mother and could get her to put in a good word for you. It’s far more likely that the pardon will be coming your way than if you were just an ordinary person with no contacts.
Anyone with several children will understand. If two of my children were to ask me for something for my third child I would be far more inclined to do it. I don’t know why it never occurs to them to gang up on me that way.
This actually gets a lot more complicated than it first appears because if having friends in high places helps your cause then that would mean God is unfair.
I believe what is really going on is that in talking with saints, which is what Catholics mean when they say praying to saints, we benefit. In the case of my children for example if they were to ask me for something for their brother or sister it helps them be better people. It forms a bond between them, it fosters love between them. God wants us to love one another. Not for some arbitrary reason, it is because we are designed that way. When we act in the way we are designed, we benefit.
Also something PGZC should seriously consider is the wisdom of dating a non Catholic. If you aren’t planning on getting married then what is the point of dating this person? If you know you won’t marry him then you know you will eventually break up with him. If you know you will break up with him you might as well do it now rather than later.
If you think you might marry this person then seriously consider what will happen to your children. Will he be willing to raise them Catholic? Does he know that you can’t use birth control or kill any “unwanted” babies? Will he interfere with you going to Church on Sundays & holy days? He will have ways to sabotage you.
Is he a good person who is honestly seeking the truth? If so then pray for him. Pray to the Holy Spirit like you have never prayed before. It works. My wife was not Catholic when I was dating her. I prayed for her conversion and it worked. I would not have married her otherwise. You can also try talking to some saints, perhaps one of them will talk to your boyfriend and knock some sense into him.
If you take your faith seriously then marrying a non Catholic would be a really big mistake. If you are a lukewarm Catholic then religion won’t be a problem.