I recently found out I had SPD. I always knew something was really wrong and it was more than just the symptoms that arise from it. But now that I know what it is; let me give you my perspective. I`ve only been in one long-term relationship and fell in love once. Since I am so shy and the social anxiety is bad, the only way I will talk to a woman is if she approaches and shows interest in me. Otherwise, I only want to be alone, in my room, by myself. My anxiety, depression, constant worrying torments so badly that my life becomes, "what can I do to make myself feel better?" Therefore, I could never really love someone the way that they might deserve and want. So the short answer is yes someone with SPD could fall in love, but don't expect them to be really too aware of and interested in how you feel, what you want, etc. You would just have to be understanding of that because people with SPD cannot express emotions well.