My ex will not drop the kids off at my house if my boyfriend is there: Advice?

My ex-husband and I have been divorced now for a year. We have four children together. I started dating. My ex knew this and who I am dating. Today my boyfriend was here when my ex pulled in the driveway to drop the kids off. He didn’t come in, and when he left, he sent me a text stating that for now on if my boyfriend is there for me to meet him at the gas station. He continued to say he doesn’t want to ever meet anyone I’m dating or wants to see them or hear about them. My ex has dated two women since our divorce. I did not act like this. I want to meet them, to know who is around my children. To have peace and us all work together for the happiness of our children. Does this ever stop or change? Will he ever stop acting like this and be mature?