how do I bring this up to my boyfriend without starting an argument?

So my boyfriend and I got together 4 years ago , things were extremely great until they got bad he was like a dream come true , so loving and caring and supportive and then I got mentally ill and I needed him and I got very clingy and emotional , he couldn't be there for me because he was in the midst of finals and his first practicum and I would constantly fight with him .. we broke up ... we ended up back together after 6 months apart and working on ourselves and we definitely are better than we were but I feel like something is missing . I love him to pieces and I don't want to break up or end the relationship . I really think just a little bit of communication will help and maybe he needs to realize some things .. I just don't want to make it seem like I'm nit picking things and that he's all to blame here . I've noticed he isn't completely back to being the loving and affectionate man I fell in love with . There are moments where I see it ... but weve been back together for 6 months , we haven't really gone on dates due to money , he hasn't bought me flowers or anything which isn't a necessity for making me feel loved but it's all things he used to do that he just stopped doing well before we broke up and it feels as if that's the norm for him now . I feel like it's lacking affection and that's something I need ... I need to feel loved . And I've talked to him a few times about this and he always gets defensive and it becomes a bit of an argument . We love each other deeply , this isn't an issue that would break the relationship .. but it's something that would help me feel fulfilled if that makes sense ? Like I want him to plan dates , I want him to buy me flowers even if it's just a $5 single rose from the market . I want him to woo me . I've done my best to make him feel loved and woo him and I feel like I'm not getting the same effort back in return .. he's under a lot of stress and I understand that but it makes him selfish in some ways and it becomes all about him , and I'm supportive and care more than anyone could even imagine about what's going on in his life . But I need to feel loved in return . How do I bring this up without starting a fight ? He's back in finals now so obviously this isn't the time to bring it up , but should I wait and see if after finals the effort picks up and he starts to become more affectionate towards me ? It's not like it only happens during finals though . It happens when he's in school and he needs to learn to juggle both a relationship and being a student .