Boyfriend

I love my boyfriend very much. But I need to vent a little. I dont know how to properly talk to my boyfriend about things that bother me with stuff in our relationship based on how he would react. Because I have tried to tell him about stuff that hurt my feelings or that I didn't agree with whatever he said or something he did or trying to help him stand up to his dad that he lives with that uses him like a doormat. I've tried to help him try to get a better job because he complained about his place of work. I just don't know how to tell him how I feel without him jumping to conclusions or him getting upset or me sounding like I'm hurting his feelings when I'm really not. Like I just want him to listen and let me get it all out and then support me or comfort me or tell me "thank you for telling me this". And I know some of you might say that it doesn't sound like a good relationship or that we should break up or something like that. But I dont wanna throw away 2 years of our relationship. I love him very much, I just don't know how to tell him my feelings and concerns without him getting upset or something like that. Please help.