I think all the advice you have been given is sound. I have travelled both alone - 6 mths in SE Asia and various return trips over the years, Central America, USA and most countries in Europe - and with a partner. The success of your trip will basically come down to the personalities you are, your attitudes and how will you mix and match. There are no hard and fast rules and it will come down to communication - how you express your needs and desires - as in any good relationship. Don’t be afraid to split up if it is going badly wrong, as staying together could sour the whole thing. I actually have enjoyed travelling alone, enjoying the freedom and choosing where I go and when. I have met loads of lovely people and that has been one of the joys. Maybe I'm just selfish. However, a good joint experience with the right person is absolute heaven and something to cherish for a long time.
As for harassment. Well, you can get it wherever you go. Probably one of my worst experiences was with an English uni graduate (who should have known better) years ago in Greece who I had to fight off!! You are bound to get followed and hassled somewhere along the line. You will by some to be interesting, intriguing, different, an easy touch, etc etc. You have to be careful and watch where you are going. I have found teeming cities some of the most problematic. I have used the ring trick a few times and a photo of kids as well as a good story can come in handy. Having said this, I have done things that most people would consider foolhardy and come away unscathed....or maybe my instincts are good, who knows!!