If we just look at your stays, the USA has no such count as the EU. A rough rule of thumb is to stay out as long as you've been in but by the time you reenter you've been away for five months so in theory that's all fine.
However, if they learn you are visiting your boyfriend for two months a time, they might think eventually you will want to marry him and they will deny entry. In fact, if you do plan to marry get the right K-1 visa. Otherwise what happens is at the border you get asked, why are you coming to visit, you say, visit. If they think marriage, you are denied. If you gain admittance and marry then you have lied about your intentions at the border so the moment you apply for a green card you are removed from the USA because of immigration fraud.
It is also possible they will just let you in. This is truly a "depends" situation. If you have documents ready (but do not present them without asking) to prove your ties to your home country, that might help especially if you get to secondary.
Remember Immigration Rule Number 1 and 2:
- Never lie to immigration
- Do not offer information unasked. (- What's the cause of your visit? - Visiting my boyfriend. Do not say: I did the same the last time.)