In love and sometimes confused. (Real long)

Hey all wonder if I can get some feedback. My awesome bf and I been together 6 months. While we've had our ups and downs I really love him with my whole heart and vise versa. I sometimes get sad overwhelming feeling like it all will end. I feel maybe I feel this way because I haven't been with someone this long in awhile and am very much in love with them. Unfortunately i deal with some depression and anxiety. Also my relationship does have some stresses at times being my bf has since mild anxiety depression and mild form of aspergers which if anyone doesn't know is mild autism. Which can be difficult to deal with. We hung out for a couple months as friends till we decided to start dating. I just fell in love with him. Now my biggest fear is due to his disability we may not work out. I hate to even think it will happen and it brings me to tears thinking of losing him. He's my best friend and my everything. Just hate I have these sad feelings. Think maybe I think these things and get sad cause of his disabilities he may not be the onesfor me but I can't imagine my life with out him. Not sure what I am really asking I guess just feedback and opinions. I can't imagine him with someone else or loving someone else. That would just kill me. Had a feeling if I did end it. I have a feeling it'd be a huge mistake.