My boyfriend and me have been in a relationship for several months. At first time we decided to be in a relationship, he told me he would travel with her ex, now she is his best friend. She is older than him 13 years old. They stayed together in 5 years including 1first year in a relationship. They ended about 10 years ago.

Over 1 month ago, I had my personal problem. I had to take some times to handle it. So, I disappeared from him in about 3 weeks. At that time, we still texted, emailed, skyped, e.g We kept in touch. And I found that he brought some women to his home, and I didn't know what they did. He told me he didn't do anything that cheated on me, or made me upset, e.g. But I couldn't believe him. He told me he was not sure that I was serious. Accordingly, he made that plan for themselves. However, I told him that I've been strongly serious about our relationship.

Now, he is travelling with her ex. He tries to explain to me that "they are just friends, she does like him, and wants him to be his boyfriend". But he doesn't want so. So confusing! I told him "I don't wanna be joykiller when they are travelling". He replied that "I does want call you". But he didn't do anything.

I am worried, actually extremely worried. What can I get through the hard time? How can I believe him? What should I do?

Please help me.

Thanks in advance.