Do your relationships always end in heartbreak? You're not alone. Around 35 per cent of Australian marriages end in divorce - and that's just couples who manage to tie the knot. When you factor in dating couples and de facto relationships, the percentage of breakups is much, much higher.

The good news is that scientists have been studying what makes couples happy using actual science. This infographic from Happify breaks down their chief findings, from optimum positive/negative interaction ratios to the importance of communication.

Dear Lovehacker, My boyfriend has been on anti-depressants for about 6 months and they have improved nearly every aspect of his life. Except for one. They affect his ability to ejaculate.

We still have sex and he says that he enjoys it, but I can't help but feel like it's me. Logically I know it's the medication but it is still beginning to affect my self esteem. Going down this thought path is destructive for our relationship, but I'm not sure what to do. Thanks, L

Dear Lovehacker, My girlfriend and I have been having pretty great sex for the two months we’ve officially been together. One thing I’ve noticed though is she’s really into talking trash -- like, REALLY into it. I mean anyone with some experience knows how to talk dirty, but this is heading into some rough AF territory I’m not 100% comfortable with.

Dear Lovehacker, My girlfriend of five months has asked how I'd feel about our relationship opening up (i.e. -- becoming polyamorous) though she hasn't fully specified what that means for us yet. I don't think I could really define myself this way, and I'm really not sure how this will affect our relationship moving forward. What should I be bracing myself for, best and worst case, and is it fair or selfish of me to consider this a dealbreaker?