Marriage.

So my boyfriend and I have been dating for almost 4 years now and have talked about marriage several times. He took me ring shopping and always told me he wanted to marry me. Now he’s saying he’s “hesitant” on marrying me because we don’t have sex when he wants..... sex used to be like a daily thing with us and now my sex drive has been MIA for about a year and a half or so. He still wants it all the time but I just don’t. He says that if we do it like twice a week he won’t be getting mad and upset like he does when I say no to sex..but we just had sex yesterday and yet today he got mad so it’s like no matter how often we have sex he’ll always get an attitude when I say no to sex. Or so it seems. So now he doesn’t really want to marry me because he doesn’t get his dick wet as often as he wishes and says “well it’s not my fault” which is hurtful because I try with him and I can’t get wet or turned on and sex is painful. I don’t know what to do. I don’t think I should be with someone who views marriage that way but I may need to check for underlying health issues on my end before I make that decision. What would you do??