Detachment problem

I recently talked to my therapist, and we concluded that I detach emotionally to protect myself, and it’s also affecting my relationships with others since I “turn off” my emotions to avoid connecting with others. Now I start to question if the guy I was seeing a month ago ended with me because he noticed that I didn’t connect with him emotionally and didn’t trust him. Kinda worried that I can‘t find anyone to have a serious relationship with since I subconsciously avoid attaching to others and not sure when I will be able to open up to others and bond. I mean, who would want to put in effort with someone that has a high chance of not returning the love you put in?