The phrase 'sick to my stomach' is used when you want to describe being deeply or physically impacted by something. If you are 'sick to your stomach' you are negatively impacted by something you have heard or learned. This is an informal expression used more in social contexts of amongst friends and family.

1. I can't believe what David did. It's enough to make you sick to your stomach!
2. I get sick to my stomach when I see children suffering in war zones on the news.

1. The way that company treats its workers makes me sick to my stomach. I don't know how they can get away with it.
2. The thought of delivering that sales pitch tomorrow is making me sick to my stomach. I really hope it goes to plan!