How to know he is right person

Hi all, i am in relationship with the guy around 4-5 year, from couple of days i stared to feel i cant be with him, i don't c future with him, i am not sure what to do next ??. my family knows about our relationship, and there are planning for wedding but i am getting 2nd thoughts about him. i am confused because of couple of reasons. 1. I am 27, i will take another couple of years to find compatible guy but don't have that much of time. 2.I have big trust issue, because of this issue, i may loos gud guy(new guy). 3.I don't want to go for arranged marriage, concept freaks me.