What do I do..

So my boyfriend and I have been dating for 6 months and we have always been really happy. Although, in the first few months after we had said that we loved each other I started to have this stupid thought and it was that I wasn’t sure if I loved him or not. With about 2 weeks of having that thought it finally went away and I’ve never been happier. But now in the past few days he’s been acting really weird and I finally talked to him about it yesterday. He said that he didn’t want to talk to me about it until he knew what was wrong because he didn’t want his stupid thoughts to hurt me. He told me that his mind was saying that he didn’t know if he was in love with me or not. We went back to his house and talked about it all and I’ve never been so afraid to lose someone. I cried pretty much the whole night with everything he said because I’ve been so nervous about what was wrong with him. He even cried. Closer to the end of the night I realized that not only had I heard these thoughts but I’ve had them. I told him all about it and I said the one thing you can do is think about everything we’ve done. Would he want to do it again? Has there been anything in your life that has pointed you into thinking this? those questions were the only thing that got me out of it, because I realized how much love I had for him and that the feeling wasn’t real, it was just a bad thought keeping me from happiness. We decided that we didn’t want any time away from each other because “time” isn’t “time”. It’s a breakup and that’s the last thing we wanted so. He said that it was to be okay and that he would do everything in his power to figure out what was wrong and that he just wanted me to act normal.

I told him to please fight for me...

After I left and went home he told me that just talking about it with me has already helped him so much and that he does love me, but I’m still so afraid to lose him. Any thoughts or advice?:(