My (49F) son (22M) lied to me about moving in with his girlfriend. Any advice?

My son graduated from college and got a job about 6 hours away. He has been working for about a year and a half now and has been dating his girlfriend for about the same time frame.

I’ve met here a few times and think she’s sweet but I barely know her. He comes home only a few times a year and has brought her around us maybe 2 or 3 times.

I have my whole family’s location and I wouldn’t stalk him or anything but every now and then his location would say the city next to his, where his gf lives.

Now, the last few weeks I haven’t seen him in that city at all. He was home two weeks ago and I straight up asked him if he moved in with his girlfriend. He looked me dead in the eyes and said no.

Fast forward to a few days ago, I was planning a trip down to see him and he confessed that he had moved in with his girlfriend two months ago and was sorry for lying.

Lying is the thing I hate most and I equate it to having a bad relationship with that person. I used to lie to my own mother as a kid and adult and we had such a terrible relationship. I don’t want that for my own son but this has upset me deeply and I have refused to speak to him ever since I found out.